Fix cross compilation for x86 targets from non-x86 #6168

Job	Run time
neoverse_build	7m 44s
msys2 (CLANG64, int64, Release)	1h 9m 5s
msys2 (MINGW32, int32, Release)	1h 13m 0s
msys2 (UCRT64, int32, Release)	1h 45m 0s
msys2 (CLANG64, int32, Release)	1h 17m 21s
msys2 (UCRT64, int32, None, mingw-w64-ucrt-x86_64, fc)	1h 37m 4s
msys2 (UCRT64, int64, Release)	1h 53m 41s
build (ubuntu-latest, gfortran, cmake)	47m 40s
build (ubuntu-latest, flang, make)	19m 12s
build (ubuntu-latest, flang, cmake)	45m 46s
cross_build (mips64el, mips64el-linux-gnuabi64, DYNAMIC_ARCH=1 TARGET=GENERIC)	9m 48s
build (macos-latest, gfortran, make)	14m 4s
cross_build (riscv64, riscv64-linux-gnu, TARGET=RISCV64_GENERIC)	7m 43s
build (macos-latest, gfortran, cmake)	40m 16s
build (ubuntu-latest, gfortran, make)	23m 45s
cross_build (mipsel, mipsel-linux-gnu, TARGET=MIPS1004K)	8m 44s
cross_build (alpha, alpha-linux-gnu, TARGET=EV4)	7m 55s
	12h 47m 48s

Provide feedback