Fix strncpy length in SP config loader

The length parameter of strncpy calls in sp_config_loader.c do not
account for the terminating null character which can cause unterminated
strings and compiler error in release build. Decrease length by one to
solve the issue.

Signed-off-by: Imre Kis <imre.kis@arm.com>
Change-Id: I1540d038482ed1ac98e2c400359516f6fd287086
1 file changed