Build system changes for CFI (Soong)

This CL makes multiples changes in preparation for platform-wide CFI.

(a) Adds a second -version-script=... to the command line
when building components that use a version script. This ensures that
__cfi_check is also exported, and allows CFI to be enabled for these
components.

(b) Adds both topdown and bottom up mutators for CFI to help propagate
dependencies correctly for components that may need CFI disabled.

(c) Fixes an issue with the mutators to correctly apply settings to
both generated variants

(d) Fixes issues when components have more than a single visibility
flag.

Bug: 30227045
Test: SANITIZE_TARGET=cfi m -j40 # dependencies are correctly built
                                 # with/without CFI

Change-Id: I44793cc03bcbcdaa957cc49c7240b87d7c9db327