EDAC: i5400_edac: get rid of some unused vars

There are several temporary unused vars:

	drivers/edac/i5400_edac.c: In function ‘i5400_get_mc_regs’:
	drivers/edac/i5400_edac.c:1058:6: warning: variable ‘maxdimmperch’ set but not used [-Wunused-but-set-variable]
	 1058 |  int maxdimmperch;
	      |      ^~~~~~~~~~~~
	drivers/edac/i5400_edac.c:1057:6: warning: variable ‘maxch’ set but not used [-Wunused-but-set-variable]
	 1057 |  int maxch;
	      |      ^~~~~
	drivers/edac/i5400_edac.c: In function ‘i5400_init_dimms’:
	drivers/edac/i5400_edac.c:1174:6: warning: variable ‘max_dimms’ set but not used [-Wunused-but-set-variable]
	 1174 |  int max_dimms;
	      |      ^~~~~~~~~
	drivers/edac/i5400_edac.c:1173:14: warning: variable ‘channel_count’ set but not used [-Wunused-but-set-variable]
	 1173 |  int ndimms, channel_count;
	      |              ^~~~~~~~~~~~~

Get rid of them.

Acked-by: Borislav Petkov <bp@alien8.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>