packaging: cross-compile for the FP6's own cores

The phone is one SoC, 4x Cortex-A520 + 4x Cortex-A720, and the package is
built for nothing else, so build for it: -march=armv8.6-a+fp16fml+aes+sha3+sm4
-mtune=cortex-a720 instead of the generic Armv8 baseline, for the daemon, the
agent and libqcomtee alike. That is gcc's own -march=native expansion on the
phone, re-based on armv8.6-a so clang can express the same set; 8.6 is the
highest level whose mandatory set the phone exposes (8.7 would assume WFxT,
9.x SVE2 - neither is in its hwcaps, and SVE2 code would SIGILL). Same string
as the fp6-img aports and kernel.

packaging/build-package.sh

@@ -76,13 +76,18 @@ retry "make sysroot" "$SRC/packaging/make-sysroot.sh" "$SYSROOT"
 # under ~/.cache/fingerprintd/libqcomtee-<target>, which is this script's
 # default output dir. Needs git, installed above.
 retry "make libqcomtee" "$SRC/packaging/make-libqcomtee.sh" \
-	--target=aarch64-alpine-linux-musl --sysroot="$SYSROOT" --march=armv8-a
+	--target=aarch64-alpine-linux-musl --sysroot="$SYSROOT" --march=armv8.6-a+fp16fml+aes+sha3+sm4
 
 # --- cross-compile the daemon; run the suites natively. The core is portable
 # by construction (no GLib, no libqcomtee, no system headers), which is what
 # lets the wire formats and state machines be tested on the build host at all.
 cd "$SRC"
-XTARGET="--target=aarch64-alpine-linux-musl --sysroot=$SYSROOT --march=armv8-a --mtune=generic"
+# The phone is one SoC, 4x Cortex-A520 + 4x Cortex-A720, so build for it (the
+# same -march goes to libqcomtee above). armv8.6-a is the highest level whose
+# mandatory set it exposes (8.7 would assume WFxT, 9.x SVE2 - neither is in
+# its hwcaps); +fp16fml+aes+sha3+sm4 are the optional extensions it has. Same
+# string as the fp6-img aports.
+XTARGET="--target=aarch64-alpine-linux-musl --sysroot=$SYSROOT --march=armv8.6-a+fp16fml+aes+sha3+sm4 --mtune=cortex-a720"
 crafter-build -- $XTARGET
 crafter-build -- --product=agent $XTARGET
 crafter-build test