EDAC/versal: Read num_csrows and num_chans using the correct bitfield macro

Fix the extraction of num_csrows and num_chans. The extraction of the
num_rows is wrong. Instead of extracting using the FIELD_GET it is
calling FIELD_PREP.

The issue was masked as the default design has the rows as 0.

Fixes: 6f15b178 ("EDAC/versal: Add a Xilinx Versal memory controller driver")
Closes: https://lore.kernel.org/all/60ca157e-6eff-d12c-9dc0-8aeab125edda@linux-m68k.org/


Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231215053352.8740-1-shubhrajyoti.datta@amd.com