C2SoftAVCEnc: Change default dimensions and frame rate

In order to support signalling lower levels, default dimensions
and frame rate are set to smaller values, such that minimum level
calculations done with default values still stay at lowest level
supported

Bug: 149360064
Bug: 151423508
Test: atest android.media.cts.MediaRecorderTest#\
      testProfileAvcBaselineLevel1
Change-Id: Ic86e5d728d99652ea4e4a46df4f46b3ff3b357ac