library: remove procps_pagesize_get()

This is actually a systemcall getpagesize(2) or it is defined
in configure using a variety of methods, including a default
hard coded value as a last resort.

There is no need to have this in libprocps

top/top.c

@@ -3253,7 +3253,7 @@ static void before (char *me) {
    // establish cpu particulars
    Hertz = procps_hertz_get();
    Cpu_cnt = procps_cpu_count();
-   Page_size = procps_pagesize_get();
+   Page_size = getpagesize();
 #ifdef PRETEND8CPUS
    Cpu_cnt = 8;
 #endif