Add entry.S function name to tag file

[Aneesh Kumar]

How about a patch like the one attached below. I am not sure whether i
got the regular expression correct. But it works for me.

-aneesh
diff --git a/Makefile b/Makefile
index 252a659..6c8479e 100644
--- a/Makefile
+++ b/Makefile
@@ -1272,7 +1272,7 @@ define cmd_tags
 	CTAGSF=`ctags --version | grep -i exuberant >/dev/null &&     \
                 echo "-I __initdata,__exitdata,__acquires,__releases  \
                       -I EXPORT_SYMBOL,EXPORT_SYMBOL_GPL              \
-                      --extra=+f --c-kinds=+px"`;                     \
+                      --extra=+f --c-kinds=+px --regex-asm=/ENTRY\(([^)]*)\).*/\1/f/"`;  \
                 $(all-sources) | xargs ctags $$CTAGSF -a
 endef