Prevent duplicated extension names from being set in Vulkan CreateInfo

[vildninja]

Fixed the code responsible for removing duplicated extension names in Hook_vkCreateDevice and Hook_vkCreateInstance, when merging ppEnabledExtensionNames with requestedDeviceExtensions and requestedInstanceExtensions.

The previous error caused a startup crash on Android for the Galaxy Tab Active3. Our newer Android devices just posts a warning.

// Logcat from Galaxy Tab Active5
D  [Vulkan init] extensions: name=VK_EXT_debug_report [enabled=0, external=0]
D  [Vulkan init] extensions: name=VK_EXT_debug_utils [enabled=1, external=0]
D  [Vulkan init] extensions: name=VK_EXT_surface_maintenance1 [enabled=0, external=0]
D  [Vulkan init] extensions: name=VK_EXT_swapchain_colorspace [enabled=1, external=0]
D  [Vulkan init] extensions: name=VK_GOOGLE_surfaceless_query [enabled=0, external=0]
D  [Vulkan init] extensions: name=VK_KHR_android_surface [enabled=1, external=0]
D  [Vulkan init] extensions: name=VK_KHR_device_group_creation [enabled=0, external=0]
D  [Vulkan init] extensions: name=VK_KHR_external_fence_capabilities [enabled=1, external=0]
D  [Vulkan init] extensions: name=VK_KHR_external_memory_capabilities [enabled=1, external=0]
D  [Vulkan init] extensions: name=VK_KHR_external_semaphore_capabilities [enabled=1, external=0]
D  [Vulkan init] extensions: name=VK_KHR_get_physical_device_properties2 [enabled=1, external=0]
D  [Vulkan init] extensions: name=VK_KHR_get_surface_capabilities2 [enabled=0, external=0]
D  [Vulkan init] extensions: name=VK_KHR_surface [enabled=1, external=0]
D  [Vulkan init] extensions: name=VK_KHR_surface_protected_capabilities [enabled=0, external=0]
// RIP Active3
I  CreateInfoWrapper::FilterExtension: already have 'VK_KHR_external_memory_capabilities'.
I  CreateInfoWrapper::FilterExtension: already have 'VK_KHR_external_semaphore_capabilities'.
I  CreateInfoWrapper::FilterExtension: already have 'VK_KHR_get_physical_device_properties2'.

Possibly related to #437 and #1120

#437 (comment)

[cla-assistant-unity]

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