spi: pxa2xx: Remove outdated documentation

The documentation is referring to the legacy enumeration of the SPI
host controllers and target devices. It has nothing to do with the
modern way, which is the only supported in kernel right now. Hence,
remove outdated documentation file.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20240417110334.2671228-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: andy-shev

Documentation/spi/pxa2xx.rst

@@ -832,8 +832,7 @@ config SPI_PXA2XX
 	select PXA_SSP if ARCH_PXA || ARCH_MMP
 	help
 	  This enables using a PXA2xx or Sodaville SSP port as a SPI master
-	  controller. The driver can be configured to use any SSP port and
-	  additional documentation can be found a Documentation/spi/pxa2xx.rst.
+	  controller. The driver can be configured to use any SSP port.
 
 config SPI_PXA2XX_PCI
 	def_tristate SPI_PXA2XX && PCI && COMMON_CLK