find_exported_dentry() declares
	char nbuf[NAME_MAX+1];
in 2 separate places, and gcc allocates space on the stack for both
of them.  Having just one of them will suffice, if we can put put
with its scope.

Reduces function stack usage on x86-32 from 0x230 to 0x130.
Signed-off-by: Randy Dunlap <rddunlap@osdl.org>
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>