Don't force building target GMP and MPFR when a native gdb is built. Rather,
add a config knob to configure the native gdb to use or not to use GMP and
MPFR; _this_config_knob_ will force building the target GMP and MPFR only if
turned on.

/trunk/scripts/build/debug/300-gdb.sh | 2 1 1 0 +-
/trunk/config/debug/gdb.in | 21 19 2 0 +++++++++++++++++++--
2 files changed, 20 insertions(+), 3 deletions(-)

 # Compute IA-64-specific values

 CT_DoArchValues() {

     # The architecture part of the tuple:

     CT_TARGET_ARCH="${CT_ARCH}${target_endian_el}"

     # Override CFLAGS for endianness:

     case "${CT_ARCH_BE},${CT_ARCH_LE}" in

         y,) CT_ARCH_ENDIAN_CFLAG="-EB";;

         ,y) CT_ARCH_ENDIAN_CFLAG="-EL";;

     esac

 }