cameraserver: Fix HIDL vs AIDL CameraBlobId discrepancy; Move HIDL into seperate source files.

- Have cameraserver fix the discrepancy between HIDL and AIDL CameraBlobId enum backing type.
- Move HIDL specific code into seperate source files (preparation for b/219020552).

Bug: 219020552
Bug: 229688810

Test: build; use GCA (basic validity)
Test: atest DngCreatorTest.java#testRaw16JpegConsistency (both HIDL and AIDL GCH)

Change-Id: I317c434d22e5e93e7e4cf5ab3aebc4efc93d2d46
Signed-off-by: Jayant Chowdhary <jchowdhary@google.com>