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/services/std_svc/psci/psci_entry.S b/services/std_svc/psci/psci_entry.S
index 73c3377..5f4f91c 100644
--- a/services/std_svc/psci/psci_entry.S
+++ b/services/std_svc/psci/psci_entry.S
@@ -48,7 +48,7 @@
 	 * On the warm boot path, most of the EL3 initialisations performed by
 	 * 'el3_entrypoint_common' must be skipped:
 	 *
-	 *  - Only when the platform bypasses the BL1/BL3-1 entrypoint by
+	 *  - Only when the platform bypasses the BL1/BL31 entrypoint by
 	 *    programming the reset address do we need to set the CPU endianness.
 	 *    In other cases, we assume this has been taken care by the
 	 *    entrypoint code.