[PATCH] uml: force using /bin/bash for building

This forces make to use bash rather than whatever /bin/sh is linked to. 
Without this, since there are some bash extensions used in the build and when
/bin/sh isn't bash, then the build fails without a clear error message.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade_spam@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/um/Makefile

@@ -5,6 +5,8 @@
 
 ARCH_DIR = arch/um
 OS := $(shell uname -s)
+#We require it or things break.
+SHELL := /bin/bash
 
 # Recalculate MODLIB to reflect the EXTRAVERSION changes (via KERNELRELEASE)
 # The way the toplevel Makefile is written EXTRAVERSION is not supposed