mm/early_ioremap.c: remove redundant early_ioremap_shutdown()

early_ioremap_reset() reserved a weak function so that architectures can
provide a specific cleanup.  Now no architectures use it, remove this
redundant function.

Link: https://lkml.kernel.org/r/20210901082917.399953-1-o451686892@gmail.com
Signed-off-by: Weizhao Ouyang <o451686892@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/asm-generic/early_ioremap.h

@@ -19,12 +19,6 @@ extern void *early_memremap_prot(resource_size_t phys_addr,
 extern void early_iounmap(void __iomem *addr, unsigned long size);
 extern void early_memunmap(void *addr, unsigned long size);
 
-/*
- * Weak function called by early_ioremap_reset(). It does nothing, but
- * architectures may provide their own version to do any needed cleanups.
- */
-extern void early_ioremap_shutdown(void);
-
 #if defined(CONFIG_GENERIC_EARLY_IOREMAP) && defined(CONFIG_MMU)
 /* Arch-specific initialization */
 extern void early_ioremap_init(void);

mm/early_ioremap.c

@@ -38,13 +38,8 @@ pgprot_t __init __weak early_memremap_pgprot_adjust(resource_size_t phys_addr,
 	return prot;
 }
 
-void __init __weak early_ioremap_shutdown(void)
-{
-}
-
 void __init early_ioremap_reset(void)
 {
-	early_ioremap_shutdown();
 	after_paging_init = 1;
 }