Remove dashes from image names: 'BL3-x' --> 'BL3x'

This patch removes the dash character from the image name, to
follow the image terminology in the Trusted Firmware Wiki page:

    https://github.com/ARM-software/arm-trusted-firmware/wiki

Changes apply to output messages, comments and documentation.

non-ARM platform files have been left unmodified.

Change-Id: Ic2a99be4ed929d52afbeb27ac765ceffce46ed76
diff --git a/include/common/el3_common_macros.S b/include/common/el3_common_macros.S
index 0514e2a..6f7136f 100644
--- a/include/common/el3_common_macros.S
+++ b/include/common/el3_common_macros.S
@@ -104,7 +104,7 @@
 
 /* -----------------------------------------------------------------------------
  * This is the super set of actions that need to be performed during a cold boot
- * or a warm boot in EL3. This code is shared by BL1 and BL3-1.
+ * or a warm boot in EL3. This code is shared by BL1 and BL31.
  *
  * This macro will always perform reset handling, architectural initialisations
  * and stack setup. The rest of the actions are optional because they might not