BufferQueue: Increase max slots from 32 to 64

Increases NUM_BUFFER_SLOTS from 32 to 64 and changes the mask
returned by IGBC::getReleasedBuffers from 32 to 64 bits.

Bug: 13174352
Change-Id: Ie8ef0853916cfb91f83881c7241886bb1950f01a
diff --git a/libs/gui/ConsumerBase.cpp b/libs/gui/ConsumerBase.cpp
index b6adc54..f1b8fa8 100644
--- a/libs/gui/ConsumerBase.cpp
+++ b/libs/gui/ConsumerBase.cpp
@@ -121,10 +121,10 @@
         return;
     }
 
-    uint32_t mask = 0;
+    uint64_t mask = 0;
     mConsumer->getReleasedBuffers(&mask);
     for (int i = 0; i < BufferQueue::NUM_BUFFER_SLOTS; i++) {
-        if (mask & (1 << i)) {
+        if (mask & (1ULL << i)) {
             freeBufferLocked(i);
         }
     }