library: relocate the typedef used in alloc.h override

There is no longer justification for placing a typedef
employed in overriding that alloc.h message handler in
the procps.h header file. So this commit just moves it
to the alloc.h header file itself where's it's needed!

[ gosh, sure wish i had thought to relocate this guy ]
[ when the changes in the 1st commit shown were made ]

Reference(s):
. most recent related changes
commit 18e5aecd2b
. place where it *should* have been relocated
commit 2865ded64e

Signed-off-by: Jim Warner <james.warner@comcast.net>

proc/alloc.h

@@ -5,6 +5,8 @@
 
 EXTERN_C_BEGIN
 
+typedef void (*message_fn)(const char *__restrict, ...) __attribute__((format(printf,1,2)));
+
  /* change xalloc_err_handler to override the default fprintf(stderr... */
 extern message_fn xalloc_err_handler;
 

proc/procps.h

@@ -87,7 +87,4 @@
 #define HIDDEN_ALIAS(x) extern __typeof(x) x##_direct __attribute__((alias(#x)))
 #endif
 
-
-typedef void (*message_fn)(const char *__restrict, ...) __attribute__((format(printf,1,2)));
-
 #endif