ARC: ioremap: use more commonly used PAGE_KERNEL based uncached flag

and remove the one off uncached definition for ARC
Signed-off-by: Vineet Gupta <vgupta@kernel.org>

arch/arc/include/asm/pgtable.h

@@ -103,9 +103,6 @@
  */
 #define PAGE_KERNEL          __pgprot(_K_PAGE_PERMS | _PAGE_CACHEABLE)
 
-/* ioremap */
-#define PAGE_KERNEL_NO_CACHE __pgprot(_K_PAGE_PERMS)
-
 /* Masks for actual TLB "PD"s */
 #define PTE_BITS_IN_PD0		(_PAGE_GLOBAL | _PAGE_PRESENT | _PAGE_HW_SZ)
 #define PTE_BITS_RWX		(_PAGE_EXECUTE | _PAGE_WRITE | _PAGE_READ)

arch/arc/mm/ioremap.c

@@ -39,7 +39,8 @@ void __iomem *ioremap(phys_addr_t paddr, unsigned long size)
 	if (arc_uncached_addr_space(paddr))
 		return (void __iomem *)(u32)paddr;
 
-	return ioremap_prot(paddr, size, pgprot_val(PAGE_KERNEL_NO_CACHE));
+	return ioremap_prot(paddr, size,
+			    pgprot_val(pgprot_noncached(PAGE_KERNEL)));
 }
 EXPORT_SYMBOL(ioremap);