GHES: Make ghes_estatus_caches static

It is used only in ghes.c.
Signed-off-by: Borislav Petkov <bp@suse.de>

drivers/acpi/apei/ghes.c

@@ -128,7 +128,7 @@ static DEFINE_SPINLOCK(ghes_ioremap_lock_irq);
 static struct gen_pool *ghes_estatus_pool;
 static unsigned long ghes_estatus_pool_size_request;
 
-struct ghes_estatus_cache *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE];
+static struct ghes_estatus_cache *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE];
 static atomic_t ghes_estatus_cache_alloced;
 
 static int ghes_ioremap_init(void)