ps: add build option to disable ps option warning

Slackware seems to have this patch, while it is not in use(?) Well,
the upstream procps-ng allows one to disable warnings if that is
wanted. After all having this sort of 'feature' does not cost much,
while lacking it might annoy someone.

A patch from Slackware.

Reference: http://www.ftp.be/packages/slackware/slackware_source/a/procps/procps.nowarning.diff.gz
Backported-by: Sami Kerola <kerolasa@iki.fi>

Conflicts:

	proc/ksym.c

configure.ac

@@ -136,6 +136,14 @@ if test "x$enable_w_from" = xyes; then
   AC_DEFINE(W_SHOWFROM, 1, [enable w from field by default])
 fi
 
+AC_ARG_ENABLE([whining],
+  AS_HELP_STRING([--disable-whining], [do not print unnessary warnings (slackware-ism)]),
+  [], enable_whining=yes
+)
+if test "x$enable_whining" = xyes; then
+  AC_DEFINE(BUILD_WITH_WHINE, 1, [should extra warnings be printed (slackware-ism)])
+fi
+
 if test x"$DEJAGNU" = x                                                        
 then                                                                           
   DEJAGNU="\$(top_srcdir)/testsuite/global-conf.exp"