*: add -Wunused-parameter; fix resulting breakage

function                                             old     new   delta
procps_scan                                         1265    1298     +33
aliascmd                                             278     283      +5
parse_file_cmd                                       116     120      +4
dname_enc                                            373     377      +4
setcmd                                                90      93      +3
execcmd                                               57      60      +3
count_lines                                           72      74      +2
process_command_subs                                 340     339      -1
test_main                                            409     407      -2
mknod_main                                           179     177      -2
handle_incoming_and_exit                            2653    2651      -2
argstr                                              1312    1310      -2
shiftcmd                                             131     128      -3
exitcmd                                               46      43      -3
dotcmd                                               297     294      -3
breakcmd                                              86      83      -3
evalpipe                                             353     349      -4
evalcommand                                         1180    1176      -4
evalcmd                                              109     105      -4
send_tree                                            374     369      -5
mkfifo_main                                           82      77      -5
evalsubshell                                         152     147      -5
typecmd                                               75      69      -6
letcmd                                                61      55      -6
add_cmd                                             1190    1183      -7
main                                                 891     883      -8
ash_main                                            1415    1407      -8
parse_stream                                        1377    1367     -10
alloc_procps_scan                                     55       -     -55
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 7/21 up/down: 54/-148)          Total: -94 bytes
   text    data     bss     dec     hex filename
 797195     658    7428  805281   c49a1 busybox_old
 797101     658    7428  805187   c4943 busybox_unstripped

runit/chpst.c

@@ -290,7 +290,7 @@ static void envdir(int, char **) ATTRIBUTE_NORETURN;
 static void softlimit(int, char **) ATTRIBUTE_NORETURN;
 
 int chpst_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int chpst_main(int argc, char **argv)
+int chpst_main(int argc ATTRIBUTE_UNUSED, char **argv)
 {
 	INIT_G();
 
@@ -349,7 +349,7 @@ int chpst_main(int argc, char **argv)
 	bb_perror_msg_and_die("exec %s", argv[0]);
 }
 
-static void setuidgid(int argc, char **argv)
+static void setuidgid(int argc ATTRIBUTE_UNUSED, char **argv)
 {
 	const char *account;
 
@@ -361,7 +361,7 @@ static void setuidgid(int argc, char **argv)
 	bb_perror_msg_and_die("exec %s", argv[0]);
 }
 
-static void envuidgid(int argc, char **argv)
+static void envuidgid(int argc ATTRIBUTE_UNUSED, char **argv)
 {
 	const char *account;
 
@@ -373,7 +373,7 @@ static void envuidgid(int argc, char **argv)
 	bb_perror_msg_and_die("exec %s", argv[0]);
 }
 
-static void envdir(int argc, char **argv)
+static void envdir(int argc ATTRIBUTE_UNUSED, char **argv)
 {
 	const char *dir;
 
@@ -385,7 +385,7 @@ static void envdir(int argc, char **argv)
 	bb_perror_msg_and_die("exec %s", argv[0]);
 }
 
-static void softlimit(int argc, char **argv)
+static void softlimit(int argc ATTRIBUTE_UNUSED, char **argv)
 {
 	char *a,*c,*d,*f,*l,*m,*o,*p,*r,*s,*t;
 	getopt32(argv, "+a:c:d:f:l:m:o:p:r:s:t:",