clk: msm: clock-gcc: Associate gfx rail voting with gfx3d branch

The root clock of gfx3d_clk_src is required to be voted on before enabling
the oxili gdscr and disabled after disabling gdscr. GFX rail can not handle
any voltage set from clk_disable_unprepare after disable of gdscr, thus
moving the rail voting with the gfx3d branch.

Change-Id: I2a1759cd059f643594d4dbc7ce0329f0e143ac43
Signed-off-by: Taniya Das <tdas@codeaurora.org>