ENGR00303663 mxc v4l2 capture: Don't return error if we cannot get mipi csi2

ENGR00303663 mxc v4l2 capture: Don't return error if we cannot get mipi csi2

The mipi csi2 code is ugly present in the capture pipeline setup/disable
routions with '#ifdef CONFIG_MXC_MIPI_CSI2/#endif' protected.  Whenever
it finds mipi_csi2_info is not gotten correctly, it will return error to
callers.  This breaks the normally routines in which mipi csi2 is not used
and mipi csi2 driver is disabled in its devicetree node(but with the
Kconfig CONFIG_MXC_MIPI_CSI2 defined).  A real example is the capture
feature on the MX6 Sabreauto platforms.  We have only parallel CSI input
on it and the mipi csi2 driver is disabled in its devicetree node but with
the Kconfig CONFIG_MXC_MIPI_CSI2 defined.  So, a reasonable choice at present
is not to return error if mipi_csi2_info cannot be gotten, though we could
eventually re-organize the capture code for a better total solution in the
future.

Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
(cherry picked from commit 8133b7fd26e8b068fa8ab9cd62eae090c76080be)