frv: hide uncached_access() when pgprot_noncached is not #defined

Hide uncached_access() when pgprot_noncached is not #defined. This prevents
the following warning:

CC drivers/char/mem.o
drivers/char/mem.c:229: warning: 'uncached_access' defined but not used

Repairs d7d4d849b4e3acc405ec222884936800ffb26d48 ("drivers/char/mem.c:
cleanups").

Signed-off-by: David Howells <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/char/mem.c

···
  * outside of main memory.
  *
  */
+#ifdef pgprot_noncached
 static int uncached_access(struct file *file, unsigned long addr)
 {
 #if defined(CONFIG_IA64)
···
 	return addr >= __pa(high_memory);
 #endif
 }
+#endif
 
 static pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 				     unsigned long size, pgprot_t vma_prot)