common: Move enable/disable_interrupts out of common.h

Move these two functions into the irq_funcs.h header file. Also move
interrupt_handler_t as this is used by the irq_install_handler() function.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/post/lib_powerpc/cr.c b/post/lib_powerpc/cr.c
index 93de47a..56ed355 100644
--- a/post/lib_powerpc/cr.c
+++ b/post/lib_powerpc/cr.c
@@ -5,6 +5,7 @@
  */
 
 #include <common.h>
+#include <irq_func.h>
 
 /*
  * CPU test