json: Allocate small arrays in-place. #3272

Job	Run time
linux deb no dpdk	5m 17s
dpdk gcc (ubuntu-24.04)	6s
libreswan (ubuntu-24.04)	5s
linux rpm fedora	4m 10s
build oss-fuzz fuzzers	3m 5s
osx clang --disable-ssl	1m 38s
clang-analyze-cache	18s
linux gcc --disable-ssl	2m 30s
linux clang --disable-ssl	2m 41s
linux gcc c99	2m 35s
linux clang c99	2m 41s
linux gcc test	8m 39s
linux clang address,undefined test	16m 44s
linux gcc test --enable-shared	11m 47s
linux clang test --enable-shared	11m 15s
linux gcc check check-dpdk dpdk	19m 10s
linux clang check check-dpdk dpdk	18m 59s
linux gcc test -ljemalloc	9m 8s
linux clang test -ljemalloc	9m 21s
linux gcc --enable-afxdp	3m 47s
linux clang --enable-afxdp	2m 35s
linux gcc dpdk --enable-shared	4m 9s
linux clang dpdk --enable-shared	4m 39s
linux gcc dpdk-shared	3m 2s
linux clang dpdk-shared	4m 21s
linux gcc dpdk-shared --enable-shared	4m 1s
linux clang dpdk-shared --enable-shared	3m 48s
linux gcc m32 --disable-ssl	2m 39s
linux gcc check-ovsdb-cluster	6m 57s
linux gcc check-kernel -100	10m 56s
linux gcc check-kernel 100-	17m 11s
linux clang address,undefined check-kernel -100	15m 28s
linux clang address,undefined check-kernel 100-	19m 46s
linux gcc check-offloads -100	10m 3s
linux gcc check-offloads 100-	12m 21s
linux gcc dpdk check-system-userspace	12m 11s
linux clang address,undefined dpdk check-system-userspace	16m 53s
linux gcc dpdk check-system-tso	12m 16s
linux gcc dpdk check-afxdp	12m 8s
clang-analyze	10m 40s
	5h 20m 0s

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