vulkan: add recursive f/n/vulkan/Android.mk

This allows using 'mm' to build everything under this dir, instead of
needing to build in each subdir separately.

Change-Id: I0c7692a7be54899b40f1cacdab3bea0e74d80174
(cherry picked from commit ba85347fc30649a17b00a237d81e8861097baeb9)
1 file changed