Replace all SCP FW (BL0, BL3-0) references

This patch replaces all references to the SCP Firmware (BL0, BL30,
BL3-0, bl30) with the image terminology detailed in the TF wiki
(https://github.com/ARM-software/arm-trusted-firmware/wiki):

    BL0          -->  SCP_BL1
    BL30, BL3-0  -->  SCP_BL2
    bl30         -->  scp_bl2

This change affects code, documentation, build system, tools and
platform ports that load SCP firmware. ARM plaforms have been
updated to the new porting API.

IMPORTANT: build option to specify the SCP FW image has changed:

    BL30 --> SCP_BL2

IMPORTANT: This patch breaks compatibility for platforms that use BL2
to load SCP firmware. Affected platforms must be updated as follows:

    BL30_IMAGE_ID --> SCP_BL2_IMAGE_ID
    BL30_BASE --> SCP_BL2_BASE
    bl2_plat_get_bl30_meminfo() --> bl2_plat_get_scp_bl2_meminfo()
    bl2_plat_handle_bl30() --> bl2_plat_handle_scp_bl2()

Change-Id: I24c4c1a4f0e4b9f17c9e4929da815c4069549e58
diff --git a/make_helpers/build_macros.mk b/make_helpers/build_macros.mk
index 08cb4b1..00fb92c 100644
--- a/make_helpers/build_macros.mk
+++ b/make_helpers/build_macros.mk
@@ -110,8 +110,8 @@
 # FIP_ADD_IMG allows the platform to specify an image to be packed in the FIP
 # using a build option. It also adds a dependency on the image file, aborting
 # the build if the file does not exist.
-#   $(1) = build option to specify the image filename (BL30, BL33, etc)
-#   $(2) = command line option for the fip_create tool (bl30, bl33, etc)
+#   $(1) = build option to specify the image filename (SCP_BL2, BL33, etc)
+#   $(2) = command line option for the fip_create tool (scp_bl2, bl33, etc)
 # Example:
 #   $(eval $(call FIP_ADD_IMG,BL33,--bl33))
 define FIP_ADD_IMG