Refactor DDS loading code #17226

Job	Run time
📊 Static checks / Code style, file formatting, and docs	37s
🍏 iOS / Template (target=template_release)	20m 48s
🤖 Android / Template (target=template_release)	27m 25s
🌐 Web / Template (target=template_release)	18m 23s
🐧 Linux / Editor w/ Mono (target=editor)	34m 34s
🐧 Linux / Editor with doubles and GCC sanitizers (target=editor, tests=yes, dev_build=yes, scu_build=yes, precision=double, use_asan=yes, use_ubsan=yes, linker=gold)	35m 6s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	30m 39s
🏁 Windows / Editor (target=editor, tests=yes)	41m 38s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	25m 55s
🍎 macOS / Editor (target=editor, tests=yes)	28m 4s
🏁 Windows / Template (target=template_release)	28m 22s
🍎 macOS / Template (target=template_release)	19m 0s
🐧 Linux / Template w/ Mono (target=template_release)	22m 35s
🐧 Linux / Minimal template (target=template_release, everything disabled)	5m 14s
🪲 Godot CPP / Build and test Godot CPP	6m 45s
	5h 45m 5s

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