msm: kgsl: Do not modify the userspace alignment request

Userspace cares about the GPU VA alignment it requested, and it does
not know about the alignment forced by the device. Do not modify the
userspace-requested alignment value since it is shared with
userspace.

Change-Id: If5e605aeb92724785ab24af5b7bf29f8138e5f46
Signed-off-by: Lynus Vaz <lvaz@codeaurora.org>