msm:camera: Fix signedness issue in hw_exec_cmds

In hw_exec_cmds()second argument m_cmds should be
of type unsigned interger

Bug: 11518040
Signed-off-by: Apurva Rajguru <arajguru@codeaurora.org>
Signed-off-by: Mekala Natarajan <mekalan@codeaurora.org>