vulkan: add more format mapping from GL formats

Test: build
Change-Id: Ie1a56115fc5eb42ef03440a3ee4faab8dd795416
diff --git a/stream-servers/vulkan/VkCommonOperations.cpp b/stream-servers/vulkan/VkCommonOperations.cpp
index 18a7d52..53bc9f6 100644
--- a/stream-servers/vulkan/VkCommonOperations.cpp
+++ b/stream-servers/vulkan/VkCommonOperations.cpp
@@ -1477,6 +1477,10 @@
         case GL_BGRA_EXT:
         case GL_BGRA8_EXT:
             return VK_FORMAT_B8G8R8A8_UNORM;
+        case GL_R16_EXT:
+            return VK_FORMAT_R16_UNORM;
+        case GL_RG8_EXT:
+            return VK_FORMAT_R8G8_UNORM;
         default:
             VK_COMMON_ERROR("Unhandled format %d, falling back to VK_FORMAT_R8G8B8A8_UNORM",
                             internalformat);