Add AHB_allocate2 + get/setDataSpace

Also fix that some ADataSpace enum values were not prefixed
with ADATASPACE_*

Test: atest AHardwareBufferTest
Bug: 315475131
Change-Id: Ie92f416a209501fa8fdc9b3593ea6d3bb68eaa48
diff --git a/libs/ui/Gralloc2.cpp b/libs/ui/Gralloc2.cpp
index e9b5dec..a5aca99 100644
--- a/libs/ui/Gralloc2.cpp
+++ b/libs/ui/Gralloc2.cpp
@@ -384,8 +384,8 @@
 
 status_t Gralloc2Allocator::allocate(std::string /*requestorName*/, uint32_t width, uint32_t height,
                                      PixelFormat format, uint32_t layerCount, uint64_t usage,
-                                     uint32_t bufferCount, uint32_t* outStride,
-                                     buffer_handle_t* outBufferHandles, bool importBuffers) const {
+                                     uint32_t* outStride, buffer_handle_t* outBufferHandles,
+                                     bool importBuffers) const {
     IMapper::BufferDescriptorInfo descriptorInfo = {};
     descriptorInfo.width = width;
     descriptorInfo.height = height;
@@ -400,6 +400,8 @@
         return error;
     }
 
+    constexpr auto bufferCount = 1;
+
     auto ret = mAllocator->allocate(descriptor, bufferCount,
                                     [&](const auto& tmpError, const auto& tmpStride,
                                         const auto& tmpBuffers) {