boot: change some arch ifdefs to feature ifdefs

The routines boot_ramdisk_high, boot_get_cmdline and boot_get_kbd
are currently enabled by various combinations of CONFIG_M68K,
CONFIG_POWERPC and CONFIG_SPARC.

Use CONFIG_SYS_BOOT_<FEATURE> defines instead.

CONFIG_SYS_BOOT_RAMDISK_HIGH
CONFIG_SYS_BOOT_GET_CMDLINE
CONFIG_SYS_BOOT_GET_KBD

Define these as appropriate in arch/include/asm/config.h files.

Signed-off-by: John Rigby <john.rigby@linaro.org>
Acked-by: Wolfgang Denk <wd@denx.de>
diff --git a/include/image.h b/include/image.h
index 18a9f0e..49d6280 100644
--- a/include/image.h
+++ b/include/image.h
@@ -340,14 +340,17 @@
 		char **of_flat_tree, ulong *of_size);
 #endif
 
-#if defined(CONFIG_PPC) || defined(CONFIG_M68K)
+#ifdef CONFIG_SYS_BOOT_RAMDISK_HIGH
 int boot_ramdisk_high (struct lmb *lmb, ulong rd_data, ulong rd_len,
 		  ulong *initrd_start, ulong *initrd_end);
-
+#endif /* CONFIG_SYS_BOOT_RAMDISK_HIGH */
+#ifdef CONFIG_SYS_BOOT_GET_CMDLINE
 int boot_get_cmdline (struct lmb *lmb, ulong *cmd_start, ulong *cmd_end,
 			ulong bootmap_base);
+#endif /* CONFIG_SYS_BOOT_GET_CMDLINE */
+#ifdef CONFIG_SYS_BOOT_GET_KBD
 int boot_get_kbd (struct lmb *lmb, bd_t **kbd, ulong bootmap_base);
-#endif /* CONFIG_PPC || CONFIG_M68K */
+#endif /* CONFIG_SYS_BOOT_GET_KBD */
 #endif /* !USE_HOSTCC */
 
 /*******************************************************************/