sh: Stub in a dummy ENTRY_OFFSET for uImage offset calculation.

If none is defined, provide a sane default, as we do for the other
options.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/boot/Makefile

@@ -18,9 +18,10 @@ CONFIG_PAGE_OFFSET	?= 0x80000000
 CONFIG_MEMORY_START	?= 0x0c000000
 CONFIG_BOOT_LINK_OFFSET	?= 0x00800000
 CONFIG_ZERO_PAGE_OFFSET	?= 0x00001000
+CONFIG_ENTRY_OFFSET	?= 0x00001000
 
 export CONFIG_PAGE_OFFSET CONFIG_MEMORY_START CONFIG_BOOT_LINK_OFFSET \
-       CONFIG_ZERO_PAGE_OFFSET
+       CONFIG_ZERO_PAGE_OFFSET CONFIG_ENTRY_OFFSET
 
 targets := zImage vmlinux.srec uImage uImage.srec
 subdir- := compressed