MSPI configuration register
| MSPI_CLK_EN | Set 1 to enable mspi clock, include mspi pll clock |
| MSPI_RST_EN | Set 0 to reset mspi module |
| MSPI_PLL_CLK_EN | Set 1 to enable mspi pll clock |
| MSPI_CLK_SEL | set this field to select clock-source. |
| MSPI_READY | Query this field after reset mspi module |