serial: 8250_dw: Drop unneeded NULL checks in dw8250_quirks()

Since platform data is being provided for all supported hardware,
no need to NULL check for it. Drop unneeded checks.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250203121456.3182891-1-andriy.shevchenko@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>