[PING] [Patch RX] Added warnings of RX variants that does not have hardware FPU support

[DJ Delorie]

These are fine, although...

+       { rx_check_float_support (); id24 (2, 0x72, sub_op << 4); F ($4, 20, 4); O4 ($2); }

the call should be on its own line, like elsewhere:

            else
              { rx_relax (RX_RELAX_BRANCH, 0);
                rx_linkrelax_branch ();
                B1 (0x39); PC2 ($2); } }

Alternatively, putting the call right after the opcode token might
make the error message point to the correct location:

float2_op
        : { rx_check_float_support (); }
	  '#' EXPR ',' REG
          { id24 (2, 0x72, sub_op << 4); F ($4, 20, 4); O4 ($2); }

Watch out for new shift-reduce warnings, though.  Sometimes you need
to put actions after distinguishing tokens to keep the parser
predictable.