SDL3 GPU: Fix -Wbool-conversion warnings #6386

Job	Run time
Create test plan	9s
level1 / Haiku	1m 39s
level2 / FreeBSD	2m 45s
level2 / Ubuntu 22.04 (Intel oneAPI)	4m 33s
level2 / Windows (MSVC, x64)	6m 11s
level2 / Ubuntu 22.04 (Intel Compiler)	3m 44s
level2 / Steam Linux Runtime 3.0 (arm64)	2m 19s
level2 / Windows (msys2, mingw64)	4m 29s
level2 / PowerPC	2m 21s
level2 / RISC OS	1m 19s
level2 / GDK (MSVC, x64)	1m 56s
level2 / Windows (MSVC, clang-cl x86)	4m 56s
level2 / Nintendo 3DS	1m 59s
level2 / Sony PlayStation Vita (GLES w/ pib)	2m 56s
level2 / NetBSD	4m 47s
level2 / Windows (MSVC, clang-cl x64)	4m 52s
level2 / Emscripten	8m 38s
level2 / LoongArch64	2m 15s
level2 / MacOS (Framework) (arm64)	2m 39s
level2 / Windows (msys2, ucrt64)	4m 36s
level2 / tvOS (CMake & xcode)	2m 2s
level2 / Ubuntu 22.04	3m 7s
level2 / Windows (msys2, clang64)	4m 29s
level2 / Windows (msys2, mingw32)	5m 0s
level2 / Android (CMake)	4m 31s
level2 / Windows (MSVC, ARM)	3m 28s
level2 / Windows (MSVC, x86)	5m 30s
level2 / Android (Android.mk)	2m 32s
level2 / Sony PlayStation Portable	4m 1s
level2 / Android (Gradle)	2m 19s
level2 / Sony PlayStation Vita (GLES w/ PVR_PSP2)	2m 51s
level2 / MacOS (Framework) (x64)	5m 13s
level2 / N-Gage	3m 56s
level2 / PowerPC64	2m 13s
level2 / Android (CMake, lean)	4m 28s
level2 / Ubuntu 24.04 (ARM64)	4m 26s
level2 / MacOS (GNU prefix)	2m 43s
level2 / Steam Linux Runtime 3.0 (x86_64)	3m 8s
level2 / iOS (CMake & xcode)	2m 6s
level2 / Windows (MSVC, ARM64)	3m 37s
level2 / Sony PlayStation 2	6m 18s
	2h 27m 1s

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