msm: kgsl: Optimize WARN() API usage in gmu driver

Instead of printing error message and then WARN_ON(1),
Use WARN() to display error message and dump call stack.

Change-Id: I07d3b374cc4df28089bacb935951cf1a672cccc7
Signed-off-by: George Shen <sqiao@codeaurora.org>
1 file changed