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/board/cobra5272/flash.c b/board/cobra5272/flash.c
index 6f36c26..1d3c5ac 100644
--- a/board/cobra5272/flash.c
+++ b/board/cobra5272/flash.c
@@ -7,6 +7,7 @@
 #include <common.h>
 #include <console.h>
 #include <cpu_func.h>
+#include <irq_func.h>
 
 #define PHYS_FLASH_1 CONFIG_SYS_FLASH_BASE
 #define FLASH_BANK_SIZE 0x200000