[ARM] 2907/1: GCC 4 serial driver compile fixes

Patch from Vincent Sanders

When building the ARM platforms several serial drivers fail to compile
with GCC 4.01 due to extern/static ambiguity.

Signed-off-by: Vincent Sanders <vince@arm.linux.org.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/serial/amba-pl010.c b/drivers/serial/amba-pl010.c
index 978e124..679e678 100644
--- a/drivers/serial/amba-pl010.c
+++ b/drivers/serial/amba-pl010.c
@@ -689,7 +689,7 @@
 	return uart_set_options(port, co, baud, parity, bits, flow);
 }
 
-extern struct uart_driver amba_reg;
+static struct uart_driver amba_reg;
 static struct console amba_console = {
 	.name		= "ttyAM",
 	.write		= pl010_console_write,