mpeg12: CB2 fix output pts error in AndroidS CTS Test. [1/1]

mpeg12: CB2 fix output pts error in AndroidS CTS Test. [1/1]

PD#SWPL-54626
BUG=199275310

Problem:
The pts information of the decoded B frame is 0, The backend will
calculate the pts of the B frame according to the duration, so that the
calculated pts information will be incorrect and cause the test to fail.

Solution:
The decoded output pts information uses the one provided by
the upper layer.

Verify:
Franklin

Change-Id: I8c273abc3e43b6777fc1bdab81208a769d52b2e5
Signed-off-by: gan.zhang <gan.zhang@amlogic.com>