refactor(plat/arm): replace FIP base and size macro with a generic name

Replaced PLAT_ARM_FIP_BASE and PLAT_ARM_FIP_MAX_SIZE macro with a
generic name PLAT_ARM_FLASH_IMAGE_BASE and PLAT_ARM_FLASH_IMAGE_MAX_SIZE
so that these macros can be reused in the subsequent GPT based support
changes.

Change-Id: I88fdbd53e1966578af4f1e8e9d5fef42c27b1173
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
diff --git a/plat/arm/common/fconf/arm_fconf_io.c b/plat/arm/common/fconf/arm_fconf_io.c
index 48286c2..ff264d2 100644
--- a/plat/arm/common/fconf/arm_fconf_io.c
+++ b/plat/arm/common/fconf/arm_fconf_io.c
@@ -18,8 +18,8 @@
 #include <platform_def.h>
 
 const io_block_spec_t fip_block_spec = {
-	.offset = PLAT_ARM_FIP_BASE,
-	.length = PLAT_ARM_FIP_MAX_SIZE
+	.offset = PLAT_ARM_FLASH_IMAGE_BASE,
+	.length = PLAT_ARM_FLASH_IMAGE_MAX_SIZE
 };
 
 const io_uuid_spec_t arm_uuid_spec[MAX_NUMBER_IDS] = {