Remove conditional enabled status on libbcc

llvm-rs-cc(and libbcc is needed by llvm-rs-cc) isn't necessary to be built when prebuilt sdk is used
(TARGET_BUILD_APPS is set without UNBUNDLED_BUILD_SDKS_FROM_SOURCE
TARGET_BUILD_UNBUNDLED_IMAGE is set)
In both cases, ALLOW_MISSING_DEPENDENCIES is set as well.
So these conditional enabled status setting is unneeded.

Bug: 165255241
Test: m clean && TARGET_BUILD_APPS=foo UNBUNDLED_BUILD_SDKS_FROM_SOURCE=true m
Change-Id: I13bdda506bbba7d41067c82657b5e0446efc8cb6
1 file changed