RISC-V: Make zicbom/zicboz errors consistent

RISC-V: Make zicbom/zicboz errors consistent

commit c818fea83de4 ("riscv: say disabling zicbom if no or bad
riscv,cbom-block-size found") improved the error messages for
zicbom but zicboz was missed since its patches were in flight
at the same time. Get 'em now.

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230918131518.56803-9-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>