Remove ifneq MINGW condition around man page uninstallation. We don't do

OS-dependent conditions in Makefiles anymore and I doubt this is correct.
If it turns out to be a problem it can easily be fixed.

Originally committed as revision 7083 to svn://svn.ffmpeg.org/ffmpeg/trunk

Makefile

@@ -164,9 +164,7 @@ uninstall-progs:
 	rm -f $(addprefix $(bindir)/, $(ALLPROGS))
 
 uninstall-man:
-ifneq ($(CONFIG_MINGW),yes)
 	rm -f $(addprefix $(mandir)/man1/,$(ALLMANPAGES))
-endif
 
 uninstall-vhook:
 	$(MAKE) -C vhook uninstall