[WIP] kernel/zarch: Fix cscal and zscal #5689

Job	Run time
neoverse_build	5m 9s
msys2 (UCRT64, int32, Release)	13m 45s
msys2 (CLANG64, int32, Release)	15m 49s
msys2 (UCRT64, int32, None, mingw-w64-ucrt-x86_64, fc)	12m 54s
msys2 (CLANG64, int64, Release)	15m 8s
build (ubuntu-latest, gfortran, make)	21m 56s
msys2 (MINGW32, int32, Release)	14m 10s
build (ubuntu-latest, gfortran, cmake)	44m 44s
build (macos-latest, gfortran, cmake)	29m 49s
msys2 (UCRT64, int64, Release)	13m 47s
build (ubuntu-latest, flang, make)	17m 59s
build (ubuntu-latest, flang, cmake)	44m 5s
cross_build (riscv64, riscv64-linux-gnu, TARGET=RISCV64_GENERIC)	2m 40s
cross_build (alpha, alpha-linux-gnu, TARGET=EV4)	2m 33s
cross_build (mipsel, mipsel-linux-gnu, TARGET=MIPS1004K)	3m 36s
build (macos-latest, gfortran, make)	10m 52s
cross_build (mips64el, mips64el-linux-gnuabi64, DYNAMIC_ARCH=1 TARGET=GENERIC)	3m 36s
	4h 32m 32s

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