RISC-V/testsuite: Add branched cases for FP cond-move operations

RISC-V/testsuite: Add branched cases for FP cond-move operations

Verify, for Ventana and Zicond targets and the ordered floating-point
conditional-move operations that already work as expected, that
if-conversion does *not* trigger at `-mbranch-cost=2' setting, which
makes original branched code sequences cheaper than their branchless
equivalents if-conversion would emit.  Cover all ordered floating-point
relational operations to make sure no corner case escapes.

	gcc/testsuite/
	* gcc.target/riscv/movdibfge-ventana.c: New test.
	* gcc.target/riscv/movdibfge-zicond.c: New test.
	* gcc.target/riscv/movdibfgt-ventana.c: New test.
	* gcc.target/riscv/movdibfgt-zicond.c: New test.
	* gcc.target/riscv/movdibfle-ventana.c: New test.
	* gcc.target/riscv/movdibfle-zicond.c: New test.
	* gcc.target/riscv/movdibflt-ventana.c: New test.
	* gcc.target/riscv/movdibflt-zicond.c: New test.
	* gcc.target/riscv/movdibfne-ventana.c: New test.
	* gcc.target/riscv/movdibfne-zicond.c: New test.
	* gcc.target/riscv/movsibfge-ventana.c: New test.
	* gcc.target/riscv/movsibfge-zicond.c: New test.
	* gcc.target/riscv/movsibfgt-ventana.c: New test.
	* gcc.target/riscv/movsibfgt-zicond.c: New test.
	* gcc.target/riscv/movsibfle-ventana.c: New test.
	* gcc.target/riscv/movsibfle-zicond.c: New test.
	* gcc.target/riscv/movsibflt-ventana.c: New test.
	* gcc.target/riscv/movsibflt-zicond.c: New test.
	* gcc.target/riscv/movsibfne-ventana.c: New test.
	* gcc.target/riscv/movsibfne-zicond.c: New test.