devtools: reduce list of Arm builds tested with meson

devtools: reduce list of Arm builds tested with meson

The list of Arm configs is growing:
	config/arm/arm64_armada_linux_gcc
	config/arm/arm64_armv8_linux_gcc
	config/arm/arm64_bluefield_linux_gcc
	config/arm/arm64_dpaa_linux_gcc
	config/arm/arm64_emag_linux_gcc
	config/arm/arm64_n1sdp_linux_gcc
	config/arm/arm64_octeontx2_linux_gcc
	config/arm/arm64_thunderx2_linux_gcc
	config/arm/arm64_thunderx_linux_gcc

In order to keep testing time reasonable,
and also because n1sdp is merged without a related fix in tests,
the list of configs is reduced in the script test-meson-builds.sh.

The list of tested Arm builds becomes:
	build-arm64-host-clang (armv8a)
	build-arm64-bluefield
	build-arm64-dpaa
	build-arm64-octeontx2

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Acked-by: David Marchand <david.marchand@redhat.com>