Revert "scripts: devicetree: Handle mixed case node names"

This reverts commit 1c060659.
Breaks cc3200_launchxl really bad:

 CC      drivers/serial/uart_cc32xx.o
/projects/zephyr4/drivers/serial/uart_cc32xx.c:39:18: error: ‘TI_CC32XX_UART_4000C000_BASE_ADDRESS’ undeclared here (not in a function)
  .base = (void *)TI_CC32XX_UART_4000C000_BASE_ADDRESS,
                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/projects/zephyr4/drivers/serial/uart_cc32xx.c: In function ‘uart_cc32xx_init’:
/projects/zephyr4/drivers/serial/uart_cc32xx.c:65:5: error: ‘TI_CC32XX_UART_4000C000_BAUD_RATE’ undeclared (first use in this function)
     TI_CC32XX_UART_4000C000_BAUD_RATE,
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Change-Id: If46c239bc8d6b4296494f638e900f6044a92ce26
Signed-off-by: Anas Nashif <anas.nashif@intel.com>