debug/gdb: update Linaro GDB revisions to 2012.04

Update Linaro GDB with the latest available revisions.

Signed-off-by: "Benoît Thébaudeau" <benoit.thebaudeau@advansee.com>

# Compute s390-specific values

CT_DoArchTupleValues() {

    # That's the only thing to override

    if [ "${CT_ARCH_64}" = "y" ]; then

        CT_TARGET_ARCH="s390x"

    fi

}