Revert "Build libcamera from source (1/3)"

Provide prebuilt froyo libcamera.so (TARGET_PREBUILT_LIBCAMERA)

This reverts commit a45ad5c9030d6cb151647e9b4a6cfbc7833fff42.

Change-Id: Ifd4c74b1d6e03e1d2cbd300593e099b122660cf4