[ARM] Add support for arch/arm/mach-*/include and arch/arm/plat-*/include

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/tools/Makefile

@@ -6,4 +6,5 @@
 
 include/asm-arm/mach-types.h: $(src)/gen-mach-types $(src)/mach-types
 	@echo '  Generating $@'
+	@mkdir -p $(dir $@)
 	$(Q)$(AWK) -f $^ > $@ || { rm -f $@; /bin/false; }