v3d: take TLB blit framebuffer dimensions from smallest surface dimensions

Typically, we program the framebuffer dimensions using the destination surface, however, if we blit a rect from a surface that is smaller than the destination, the simulator will complain that the TLB load stride is not large enough to match the destination framebuffer. We can work around this by programming the smallest size of both surfaces, which should be okay because the tlb blit path requires that the blit coordinates are the same for both src and dst.

Fixes assert crashes for MSAA tests in: ./bin/gl-1.0-logicop