msm: vidc: Initialize 10bit bw variable

In certain scenarios, y_bw_no_ubwc_10bpp and y_bw_10bpp_p010
will be used with unitialized and incorrect values.

CRs-Fixed: 2487664
Change-Id: I292ed33b60c3994886bb3756babc8ab706ceab8b
Signed-off-by: Chinmay Sawarkar <chinmays@codeaurora.org>