kbuild: fix toplevel Makefile/depmod

This removes a syntax error (seen building on Ubuntu Feisty).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

Makefile

@@ -1505,7 +1505,7 @@ quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files))
 # and we build for the host arch
 quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
       cmd_depmod = \
-	if [ -r System.map -a -x $(DEPMOD) -a "$(SUBARCH)" == "$(ARCH)" ]; then \
+	if [ -r System.map -a -x $(DEPMOD) -a "$(SUBARCH)" = "$(ARCH)" ]; then \
 		$(DEPMOD) -ae -F System.map                                     \
 		$(if $(strip $(INSTALL_MOD_PATH)), -b $(INSTALL_MOD_PATH) -r)   \
 		$(KERNELRELEASE);                                               \