libs: enc: h265: reset num_ref_idx_l1_active_minus1 when low delay B.

When enable low delay B, the reference list 1 will be same with
reference list 0, so need reset the num_ref_idx_l1_active_minus1
to num_ref_idx_l0_active_minus1.

Fixes: #160
6 jobs for ref in 12 minutes and 42 seconds (queued for 1 second)
Status Job ID Name Coverage
  Preparation
passed #301394
gst indent

00:00:19

passed #301393
manifest

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  Build
passed #301395
build fedora x86_64

00:04:38

passed #301396
build nodebug fedora x86_64

00:04:31

 
  Test
passed #301397
check fedora

00:03:57

 
  Deploy
passed #301398
documentation

00:03:35