drm: msm: hw ctl needs to care reserved pipe

When kernel operates hw ctls, early RVC in bootloader
can also co-exist to update hardware registers. So it's
needed to care the reserved pipe by early RVC before
kernel starts to handle ctl setup.

CRs-Fixed: 2225630
Change-Id: I2df06350a44bd128dfb89cc0668c41d2edfb26a6
Signed-off-by: Guchun Chen <guchunc@codeaurora.org>