android: enable building static version of libdrm

Android needs libdrm built statically for recovery;
enable that as well.

Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Chih-Wei Huang <cwhuang@linux.org.tw>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>