Added linux kernel checkpatch.pl script and stylecheck target.

To make it easier on everyone to keep a uniform coding style throughout
the project we will be using this target to verify our code for
complience.

Currently a lot of files in the project don't fully follow the coding
style. We need to reach that spot over time though. :)

Makefile

@@ -20,6 +20,9 @@
 PREFIX		?= arm-none-eabi
 #PREFIX		?= arm-elf
 
+STYLECHECK      := scripts/checkpatch.pl
+STYLECHECKFLAGS := --no-tree -f
+
 ifeq ($(DETECT_TOOLCHAIN),)
 DESTDIR		?= /usr/local
 else
@@ -96,5 +99,12 @@ clean: cleanheaders
 	@printf "  CLEAN   doxygen\n"
 	$(Q)$(MAKE) -C doc clean
 
-.PHONY: build lib $(LIB_DIRS) install doc clean generatedheaders cleanheaders
+stylecheck:
+	$(Q)for i in `find . -name '*.[ch]'` ; do \
+		if ! grep -q "* It was generated by the irq2nvic_h script." $$i ; then \
+			$(STYLECHECK) $(STYLECHECKFLAGS) $$i || exit $?; \
+		fi ; \
+	done
+
+.PHONY: build lib $(LIB_DIRS) install doc clean generatedheaders cleanheaders stylecheck