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/bl31/bl31.mk b/bl31/bl31.mk
index 0c2b631..8951159 100644
--- a/bl31/bl31.mk
+++ b/bl31/bl31.mk
@@ -62,7 +62,7 @@
 BL31_LINKERFILE		:=	bl31/bl31.ld.S
 
 # Flag used to inidicate if Crash reporting via console should be included
-# in BL3-1. This defaults to being present in DEBUG builds only
+# in BL31. This defaults to being present in DEBUG builds only
 ifndef CRASH_REPORTING
 CRASH_REPORTING		:=	$(DEBUG)
 endif