xconfig: use pkgconfig to find moc

Various schemes exist to allow parallel installations of multiple major
versions of Qt (4.x with the previous 3.x and/or the upcoming 5.x).
QtCore.pc includes a moc_location variable which should be a more reliable
way to find moc.

Signed-off-by: Yaakov Selkowitz <yselkowitz@users.sourceforge.net>
Signed-off-by: Michal Marek <mmarek@suse.cz>
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index 7966265..5e2176c 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -260,8 +260,8 @@
 	else \
 	  cflags="\$$(shell pkg-config QtCore QtGui Qt3Support --cflags)"; \
 	  libs="\$$(shell pkg-config QtCore QtGui Qt3Support --libs)"; \
-	  binpath="\$$(shell pkg-config QtCore --variable=prefix)"; \
-	  moc="$$binpath/bin/moc"; \
+	  moc="\$$(shell pkg-config QtCore --variable=moc_location)"; \
+	  [ -n "$$moc" ] || moc="\$$(shell pkg-config QtCore --variable=prefix)/bin/moc"; \
 	fi; \
 	echo "KC_QT_CFLAGS=$$cflags" > $@; \
 	echo "KC_QT_LIBS=$$libs" >> $@; \