Replace shared_lib with header_lib

libcamera_metadata was linking with libcutils for the sole purpose of
accessing its headers, specifically <cutils/compiler.h>.
Replace that with libcutils_headers, and export those headers too for
any dependencies that relied on it exporting the libcutils headers.

Test: build
Change-Id: I82298fe9829cd3996cdc6848c24685c15c7bc160
1 file changed