Camera: Don't override extension surface native format

Avoid overriding the native extension surface format when
retrieving the surface parameters.
The native surface format can later be used to configure
the device extension so the original value must be known.

Bug: 195366395
Test: atest -c
cts/tests/camera/src/android/hardware/camera2/cts/CameraExtensionSessionTest.java

Change-Id: I52d091fd782dc9ca2af60ba42ec1c5bbe080c1ca