hwc: allow DMA pipe in BLOCK mode for virtual dpy

For portrait videos case on WFD, driver supports multiplexing
of DMA pipe in LINE and BLOCK mode.
Loosen the requirements to allow DMA pipe in block mode for
portrait case of virtual display.

Change-Id: I5821501f89b17bb2d29c425aee0a6c16b2a4783b
diff --git a/libhwcomposer/hwc_utils.cpp b/libhwcomposer/hwc_utils.cpp
index f32ad34..977cf0e 100644
--- a/libhwcomposer/hwc_utils.cpp
+++ b/libhwcomposer/hwc_utils.cpp
@@ -1685,9 +1685,9 @@
     if(qdutils::MDPVersion::getInstance().is8x26() &&
             ctx->mVirtualDisplay->isConnected() &&
             !ctx->dpyAttr[HWC_DISPLAY_VIRTUAL].isPause) {
-        // Allow if YUV needs rotation and DMA is configured to BLOCK mode for
-        // primary. For portrait videos usecase on WFD, Driver supports
-        // multiplexing of DMA pipe in LINE and BLOCK mode.
+        /* 8x26 mdss driver supports multiplexing of DMA pipe
+         * in LINE and BLOCK modes for writeback panels.
+         */
         if(dpy == HWC_DISPLAY_PRIMARY)
             return false;
     }