disp: msm: sde: remove check comparing encoder's crtc and crtc

This change removes the check comparing encoder's crtc to the
crtc passed in. This check was required up until commit 70486d20
("disp: msm: sde: remove vblank cache logic"). Now that iteration
is only happening over encoders in the encoder mask, there is no
need to check for a matching crtc to ensure it is valid.

Change-Id: I4ee08061e6c8679fe03f42cf2f889704c99526e5
Signed-off-by: Samantha Tran <samtran@codeaurora.org>