media: Better compatibility with new KGSL

 * Memset the params struct instead of initializing every value manually
   so that we don't have to deal with the flags/reserved change.

Change-Id: I0085d14e7f39304936534518a6adb9c8c9544b86
media: Better ION version compatibility

Change-Id: I2eb1887ecbe7a0000d2a16768b46004d92f18a82