i386 bootioremap / kexec fix

With CONFIG_PHYSICAL_START set to a non default values the i386
boot_ioremap code calculated its pte index wrong and users of boot_ioremap
have their areas incorrectly mapped (for me SRAT table not mapped during
early boot).  This patch removes the addr < BOOT_PTE_PTRS constraint.
Signed-off-by: Keith Mannthey <kmannth@us.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

arch/i386/mm/boot_ioremap.c

@@ -30,8 +30,11 @@
  */
 
 #define BOOT_PTE_PTRS (PTRS_PER_PTE*2)
-#define boot_pte_index(address) \
-	     (((address) >> PAGE_SHIFT) & (BOOT_PTE_PTRS - 1))
+
+static unsigned long boot_pte_index(unsigned long vaddr)
+{
+	return __pa(vaddr) >> PAGE_SHIFT;
+}
 
 static inline boot_pte_t* boot_vaddr_to_pte(void *address)
 {