Fixed HDR Vulkan bugs

Fixed bug where builtin scanlines were not being turned off when certain shaders are loaded 
Fixed bug where shaders were turned off the builtin HDR shader was not applied

Author: MajorPainTheCactus

gfx/drivers/vulkan.c

@@ -3206,7 +3206,7 @@ static bool vulkan_init_default_filter_chain(vk_t *vk)
       {
          vulkan_set_hdr_inverse_tonemap(vk, vk->filter_chain_default, true);
          vulkan_set_hdr10(vk, vk->filter_chain_default, true);
-         vulkan_filter_chain_set_subpixel_layout(vk->filter_chain_default, 0.0f);
+         vulkan_filter_chain_set_scanlines(vk->filter_chain_default, 0.0f);
          settings->bools.video_hdr_scanlines = false;
          vk->flags |= VK_FLAG_SHOULD_RESIZE;
       }
@@ -4770,6 +4770,7 @@ static bool vulkan_frame(void *data, const void *frame,
          ? vulkan_filter_chain_get_pass_rt_format(filter_chain, shader_preset->passes - 1)
          : vk->context->swapchain_format;
    bool use_main_buffer           = vulkan_is_hdr10_format(back_buffer_format) && 
+      (shader_preset && shader_preset->passes) &&
       (filter_chain && !vulkan_filter_chain_emits_hdr10(filter_chain));     /* this is used when presets use scale_type in their last pass */
 #endif /* VULKAN_HDR_SWAPCHAIN */