msm: kgsl: Add GPU bus governor from 4.14 to 4.19

Adding a snapshot of the devfreq files on 4.14 as of
commit 9ac69cf (clk: qcom: gcc: Support code for clock
controller for sdxprairie).

Change-Id: Ib9491280c14f0ec0ff1c3b34aba5ce1e4f510b54
Signed-off-by: Urvashi Agrawal <urvaagra@codeaurora.org>