common: Move old EEPROM functions into a new header

These functions do not use driver model but are still used. Move them to a
new eeprom.h header file.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/board/softing/vining_fpga/socfpga.c b/board/softing/vining_fpga/socfpga.c
index d70c22f..5a88b6c 100644
--- a/board/softing/vining_fpga/socfpga.c
+++ b/board/softing/vining_fpga/socfpga.c
@@ -4,6 +4,7 @@
  */
 
 #include <common.h>
+#include <eeprom.h>
 #include <env.h>
 #include <init.h>
 #include <status_led.h>