skia: Conditionally link QC opt library
skia: Conditionally link QC opt library

 * So far this is in use by 8994 only, but that will likely change.

Change-Id: I5a003ad2fe06c21b315a5e6dfafb3b3deaffa50d
Signed-off-by: Chet Kener <4bada73e411a9c678a318a79d04d7df4a5fc4429@gmail.com>

UBERMALLOW/external_skia,UBERMALLOW/external_skia,MinimalOS-AOSP/platform_external_skia,UBERMALLOW/external_skia,MinimalOS-AOSP/platform_external_skia,MinimalOS-AOSP/platform_external_skia,UBERMALLOW/external_skia,MinimalOS-AOSP/platform_external_skia,UBERMALLOW/external_skia,MinimalOS-AOSP/platform_external_skia,MinimalOS-AOSP/platform_external_skia,UBERMALLOW/external_skia,UBERMALLOW/external_skia,UBERMALLOW/external_skia,MinimalOS-AOSP/platform_external_skia,MinimalOS-AOSP/platform_external_skia,UBERMALLOW/external_skia,MinimalOS-AOSP/platform_external_skia