msm: camera: Fix camera crash in msm_open_config

Add proper check before accessing mctl handle to
avoid camera crash.

Change-Id: I1413f086ab7d94fe223a814bb16867d1dcc0a4bf
CRs-Fixed: 481757
Signed-off-by: Suresh Vankadara <svankada@codeaurora.org>
msm: camera: Fix camera crash when ctrl_q is empty

Add proper error condition if the list is empty and
return error value to upper layers instead of BUG_ON.

Change-Id: I89237e7a27d5fb1e1fd5f1a8a2dfd7ea9a1afff5
CRs-Fixed: 481759
Signed-off-by: Suresh Vankadara <svankada@codeaurora.org>
msm: camera: Fix mctl release crash issue.

After mctl release initialize pointer to NULL to
avoid crash.

Change-Id: Ia3e0b1b809f85760a92b5248f402df589c6ace04
Signed-off-by: Suresh Vankadara <svankada@codeaurora.org>
 msm:camera: Fix overflow issue in ioctl_hw_cmds function

    'len' is of type signed int 32bit,but the assigned value
    may exceed maximum unsigned int32 range.Add overflow check
    and graceful exit if 'm'exceeds UINT32_MAX value.

Change-Id: I38f0d10a0cb44d08d0054f91044fc891c246ebd1
CRs-Fixed: 493314
Signed-off-by: Monika Alekhya <malekh@codeaurora.org>
msm:camera: Fix signedness issue in hw_exec_cmds

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

Change-Id: Idad2eb1a59481f3fe9f90221ff2061e8dae57013
CRs-Fixed: 493314
Signed-off-by: Monika Alekhya <malekh@codeaurora.org>