graphics common: fix AIDL BufferUsage calculation

This was hitting integer sanitization, which we are trying to turn on:
Before:
    VENDOR_MASK_HI = -65536L,
After:
    VENDOR_MASK_HI = -281474976710656L,

Bug: 148149098
Test: manually check output (see above).
Change-Id: I1e2d7c0225aec8bf67375eb6b0cdc919b4ece847

graphics/common/aidl/android/hardware/graphics/common/BufferUsage.aidl

@@ -110,5 +110,5 @@ enum BufferUsage {
 
     /** bits 32-47 must be zero and are reserved for future versions */
     /** bits 48-63 are reserved for vendor extensions */
-    VENDOR_MASK_HI                     = 0xffff << 48,
+    VENDOR_MASK_HI                     = (1L * 0xffff) << 48,
 }