Move a comment line which accidentally added a whitespace to the end of
SP_PACKAGING_METHOD default value.

Fixes: db9b8f09 ("fvp: add support for Secure Partitions in the FIP")
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Balint Dobszay <balint.dobszay@arm.com>