EDAC/ghes: Change ghes_hw from global to static

Smatch reports this issue
  ghes_edac.c:44:3: warning: symbol 'ghes_hw' was not declared. Should it be static?

ghes_hw is used only in ghes_edac.c so change its storage-class
specifier to static.
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220421135319.1508754-1-trix@redhat.com

drivers/edac/ghes_edac.c

@@ -38,7 +38,7 @@ static struct ghes_pvt *ghes_pvt;
  * This driver's representation of the system hardware, as collected
  * from DMI.
  */
-struct ghes_hw_desc {
+static struct ghes_hw_desc {
 	int num_dimms;
 	struct dimm_info *dimms;
 } ghes_hw;