[RenderScript] Fix IntrinsicConvolve documentation.

Bug: 25117120

  - Better format.
  - Typo fixes.

Change-Id: Ic6f8d1dacecdaf9993dd8298de7a801f5fd2a937
(cherry picked from commit 3d23dce43330b9c8f3fba34ef9515dca7912768a)
2 files changed