mimxrt/boards/ADAFRUIT_METRO_M7: Reduce flash freq to 100MHz.

It was set to 133Mhz, but that is not stable.  Reduce to 100MHz.

The UF2 bootloader runs at 100MHz, so no need for a change of the
bootloader.

Signed-off-by: robert-hh <robert@hammelrath.com>

Author: robert-hh

ports/mimxrt/boards/ADAFRUIT_METRO_M7/mpconfigboard.mk

@@ -4,7 +4,7 @@ MCU_VARIANT = MIMXRT1011DAE5A
 MICROPY_FLOAT_IMPL = single
 MICROPY_HW_FLASH_TYPE ?= qspi_nor_flash
 MICROPY_HW_FLASH_SIZE ?= 0x800000  # 8MB
-MICROPY_HW_FLASH_CLK = kFlexSpiSerialClk_133MHz
+MICROPY_HW_FLASH_CLK = kFlexSpiSerialClk_100MHz
 MICROPY_HW_FLASH_QE_CMD = 0x31
 MICROPY_HW_FLASH_QE_ARG = 0x02