[PATCH] kbuild: allow cscope to index multiple architectures

I have a single source tree which I cross compile for a couple of
different architectures using ARHC=foo O=blah etc.

The existing cscope target is very handy but only indexes the current
$(ARCH), which is a pain since inevitably I'm interested in the other
one at any given time ;-). This patch allows me to pass a list of
architectures for cscope to index. e.g.
	make ALLSOURCE_ARCHS="i386 arm" cscope

This change also works for etags etc, and I presume it is just as useful
there.
Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

Makefile

@@ -1159,19 +1159,25 @@ else
 __srctree = $(srctree)/
 endif
 
+ALLSOURCE_ARCHS := $(ARCH)
+
 define all-sources
 	( find $(__srctree) $(RCS_FIND_IGNORE) \
 	       \( -name include -o -name arch \) -prune -o \
 	       -name '*.[chS]' -print; \
-	  find $(__srctree)arch/$(ARCH) $(RCS_FIND_IGNORE) \
-	       -name '*.[chS]' -print; \
+	  for ARCH in $(ALLSOURCE_ARCHS) ; do \
+	       find $(__srctree)arch/$${ARCH} $(RCS_FIND_IGNORE) \
+	            -name '*.[chS]' -print; \
+	  done ; \
 	  find $(__srctree)security/selinux/include $(RCS_FIND_IGNORE) \
 	       -name '*.[chS]' -print; \
 	  find $(__srctree)include $(RCS_FIND_IGNORE) \
 	       \( -name config -o -name 'asm-*' \) -prune \
 	       -o -name '*.[chS]' -print; \
-	  find $(__srctree)include/asm-$(ARCH) $(RCS_FIND_IGNORE) \
-	       -name '*.[chS]' -print; \
+	  for ARCH in $(ALLSOURCE_ARCHS) ; do \
+	       find $(__srctree)include/asm-$${ARCH} $(RCS_FIND_IGNORE) \
+	            -name '*.[chS]' -print; \
+	  done ; \
 	  find $(__srctree)include/asm-generic $(RCS_FIND_IGNORE) \
 	       -name '*.[chS]' -print )
 endef