fix(nxp-ddr): fix coverity issue

Fixed coverity issue for "shifting by a negtive value", returned
before go to the next shifting code.

Signed-off-by: Jiafei Pan <Jiafei.Pan@nxp.com>
Change-Id: I00171b057b8948cb9e9ec5d9405b2e32aba568fb
1 file changed