mimxrt: Rework flash configuration.

- Moves definition of BOARD_FLASH_SIZE and other header files related to
	flash configuration into the Makefile.
- Adds board specific clock_config.h.
- Adds board.h, pin_mux.h, and peripherals.h as they are
	required by NXP MCU SDK in order to use our own clock_config.h.
- Renames board specific FlexSPI configuration files.
- Updates flash frequency of MIMXRT1020_EVK
- Creates separated flash_config files for QSPI NOR and
	QSPI Hyper flash.
- Unifies VFS start address to be @ 1M for 1010 and 1020 boards.
- Unifies 1050EVK boards
- Adds support to both NOR and HyperFlash on boards with
	both capabilities.
- Adds automatic FlexRAM initialization to start-up code based on
	linker script and NXP HAL.
- Applies code formatting to all files in mimxrt port.

With this change the flash configuration is restructured and
organized. This simplifies the configuration process and
provides a better overview of each board's settings. With the integration
of clock_config.h, board.h, pin_mux.h, and peripherals.h we gain better
control of the settings and clock configurations. Furthermore the
implementation of an explicit FlexRAM setup improves the system
performance and allows for performance tuning.

Signed-off-by: Philipp Ebensberger

tools/codeformat.py

@@ -52,6 +52,7 @@ PATHS = [
     "examples/**/*.py",
     "extmod/**/*.py",
     "ports/**/*.py",
+    "ports/mimxrt/**/*.[ch]",
     "py/**/*.py",
     "tools/**/*.py",
     "tests/**/*.py",