[PATCH] RISC-V: Fix PR109399 VSETVL PASS bug

        PR 109399

gcc/ChangeLog:

	* config/riscv/riscv-vsetvl.cc
	(pass_vsetvl::compute_local_backward_infos): Update user vsetvl in local
	demand fusion.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/vsetvl/pr109399.c: New test.