[SurfaceFlinger] Respect HDR data space.

Respect HDR data space when there is no legacy HDR support. Previously we only
cared about HDR data space when it is supported, however, on Pixel 2 there is
no HDR mode support. This patch makes sure that when HDR mode is not supported,
we fall back to Display P3 color mode correctly.

BUG: 80404330
Test: Build, flash and watch Youtube HDR
Change-Id: I7d27711fe4d33268e5ebbd14fce0975f9e642e84
Merged-In: I7d27711fe4d33268e5ebbd14fce0975f9e642e84