mmc: mmc_spi: generate R1 response for different mmc SPI commands

R1 response is 1 byte long for mmc SPI commands as per the updated
physical layer specification version 7.10.

So correct the resp and resp_size for existing commands

Signed-off-by: Pragnesh Patel <pragnesh.patel@sifive.com>
Reviewed-by: Bin Meng <bin.meng@windriver.com>
Tested-by: Bin Meng <bin.meng@windriver.com>