Added OV7675 support

[ShawnHymel]

• Added parameter to begin() that allows users to select between OV7670 and OV7675. The default is set to OV7670, so it should not break any previous code that relies on this library.
• Added conditional return to bits/bytes per pixel functions so that grayscale bits/bytes per pixel are reported correctly.
• Tested successfully on an OV7675.

[CLAassistant]

All committers have signed the CLA.

[github-actions[bot]]

Memory usage change @ 743e8d8bff26ea3d91402bc1b145016ebf4e932c

Board	flash	%	RAM for global variables	%
arduino:mbed_nano:nano33ble	:small_red_triangle: 0 - +64	0.0 - +0.01	0 - 0	0.0 - 0.0

Click for full report table

Board|examples/CameraCapture
flash|%|examples/CameraCapture
RAM for global variables|%|examples/CameraCaptureRawBytes
flash|%|examples/CameraCaptureRawBytes
RAM for global variables|%|examples/CameraTestPattern
flash|%|examples/CameraTestPattern
RAM for global variables|%|examples/ConnectionTest
flash|%|examples/ConnectionTest
RAM for global variables|% -|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|- arduino:mbed_nano:nano33ble|0|0.0|0|0.0|64|0.01|0|0.0|64|0.01|0|0.0|0|0.0|0|0.0

Click for full report CSV

``` Board,examples/CameraCapture
flash,%,examples/CameraCapture
RAM for global variables,%,examples/CameraCaptureRawBytes
flash,%,examples/CameraCaptureRawBytes
RAM for global variables,%,examples/CameraTestPattern
flash,%,examples/CameraTestPattern
RAM for global variables,%,examples/ConnectionTest
flash,%,examples/ConnectionTest
RAM for global variables,% arduino:mbed_nano:nano33ble,0,0.0,0,0.0,64,0.01,0,0.0,64,0.01,0,0.0,0,0.0,0,0.0 ```

[facchinm]

Sorry to be late to the party but I missed this :disappointed: Merging, thank you very much!