ACPI: tables: complete searching upon RSDP w/ bad checksum.

ACPI tables follow a tree structure in memory.
The root of the tree is the RSDP (Root System Description Pointer).

To find the RSDP, the OS searches for the signature "RSD PTR "
in well known physical memory locations.  Then the OS computes
a table checksum to verify that the signature is really part
of a valid table header.

Some systems have a proper signature but an invalid checksum;
followed elsewhere by a proper signature with valid checksum.

http://bugzilla.kernel.org/show_bug.cgi?id=9444

The Linux RSDP scanning code bailed out on those systems
and as a result they booted with ACPI disabled.

Fix this by deleting the Linux RSDP scanning code and
plugging in the ACPICA RSDP scanning code.

Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/tables/tbxfroot.c b/drivers/acpi/tables/tbxfroot.c
index cf8fa51..9ecb4b6 100644
--- a/drivers/acpi/tables/tbxfroot.c
+++ b/drivers/acpi/tables/tbxfroot.c
@@ -100,7 +100,7 @@
 
 /*******************************************************************************
  *
- * FUNCTION:    acpi_tb_find_rsdp
+ * FUNCTION:    acpi_find_root_pointer
  *
  * PARAMETERS:  table_address           - Where the table pointer is returned
  *
@@ -219,8 +219,6 @@
 	return_ACPI_STATUS(AE_NOT_FOUND);
 }
 
-ACPI_EXPORT_SYMBOL(acpi_find_root_pointer)
-
 /*******************************************************************************
  *
  * FUNCTION:    acpi_tb_scan_memory_for_rsdp