gguf: fix potential infinite loops while parsing #6413

Job	Run time
ubuntu-focal-make	1m 23s
ubuntu-latest-cmake	1m 25s
ubuntu-latest-cmake-mpi (mpich)	1m 26s
ubuntu-latest-cmake-sanitizer (ADDRESS, Debug)	3m 45s
ubuntu-latest-cmake-mpi (libopenmpi-dev)	1m 36s
ubuntu-latest-cmake-sanitizer (ADDRESS, Release)	3m 29s
ubuntu-latest-cmake-sanitizer (THREAD, Debug)	7m 55s
macOS-latest-cmake	4m 5s
ubuntu-latest-cmake-sanitizer (THREAD, Release)	4m 50s
macOS-latest-cmake-ios	18s
ubuntu-latest-cmake-sanitizer (UNDEFINED, Debug)	3m 13s
ubuntu-latest-cmake-sanitizer (UNDEFINED, Release)	3m 25s
macOS-latest-cmake-tvos	20s
macOS-latest-make	3m 6s
macOS-latest-swift (generic/platform=macOS)	2s
windows-latest-cmake (noavx, -DLLAMA_NATIVE=OFF -DLLAMA_BUILD_SERVER=ON -DLLAMA_AVX=OFF -DLLAMA_A...	2m 26s
windows-latest-cmake-cublas (12.2.0, cublas)	21m 38s
macOS-latest-swift (generic/platform=iOS)	13s
windows-latest-cmake (avx2, -DLLAMA_NATIVE=OFF -DLLAMA_BUILD_SERVER=ON -DBUILD_SHARED_LIBS=ON)	3m 0s
windows-latest-cmake-cublas (11.7.1, cublas)	16m 26s
windows-latest-cmake (avx, -DLLAMA_NATIVE=OFF -DLLAMA_BUILD_SERVER=ON -DLLAMA_AVX2=OFF -DBUILD_SH...	2m 31s
macOS-latest-swift (generic/platform=tvOS)	1s
windows-latest-cmake (avx512, -DLLAMA_NATIVE=OFF -DLLAMA_BUILD_SERVER=ON -DLLAMA_AVX512=ON -DBUIL...	4m 56s
windows-latest-cmake (clblast, -DLLAMA_NATIVE=OFF -DLLAMA_BUILD_SERVER=ON -DLLAMA_CLBLAST=ON -DBU...	1m 37s
windows-latest-cmake (openblas, -DLLAMA_NATIVE=OFF -DLLAMA_BUILD_SERVER=ON -DLLAMA_BLAS=ON -DBUIL...	2m 18s
release	0s
	1h 35m 24s

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