aarch64: add BTI flag to ELF notes (#822) When a program is loaded and linked, the first ELF file that doesn't declare that BTI is supported in the GNU NOTES section disables BTI support. Example: readelf -n ./aarch64-unknown-linux-gnu/.libs/libffi.so Displaying notes found in: .note.gnu.property Owner Data size Description GNU 0x00000010 NT_GNU_PROPERTY_TYPE_0 Properties: AArch64 feature: BTI Fixes: #823 Signed-off-by: Bill Roberts <bill.roberts@arm.com>