drm/msm/sde: fix INTF_2 TEAR_IRQ register index

Currently both INTF_1 and INTF_2 TEAR_IRQs are pointing
to the same register index, resulting in wrong programming.
Fix the register index value for the INTF_2 IRQ registers
in sde_intr_set table.

Change-Id: I887fa57d31fd712d5d7937137b73aaa340173be6
Signed-off-by: Veera Sundaram Sankaran <veeras@codeaurora.org>