Eliminate -Wall from being hardcoded

Author: Ralph Castain

opal/mca/pmix/pmix3x/pmix/src/Makefile.am

@@ -81,4 +81,3 @@ endif
 MAINTAINERCLEANFILES = Makefile.in config.h config.h.in
 DISTCLEANFILES = Makefile
 CLEANFILES = core.* *~
-AM_CFLAGS = -Wall