Currently the memory region is not released the folowing error is
observed.

/testsuites # insmod omap-serial.ko
[  130.746917] omap_uart omap_uart.0: memory region already claimed
[  130.753143] omap_uart: probe of omap_uart.0 failed with error -16
[  130.759338] omap_uart omap_uart.1: memory region already claimed
[  130.765380] omap_uart: probe of omap_uart.1 failed with error -16
[  130.771606] omap_uart omap_uart.2: memory region already claimed
[  130.777679] omap_uart: probe of omap_uart.2 failed with error -16
[  130.783905] omap_uart omap_uart.3: memory region already claimed
[  130.789947] omap_uart: probe of omap_uart.3 failed with error -16

Fix it by releasing the memory region.

Cc: Govindraj.R <redacted>
Signed-off-by: Shubhrajyoti D <redacted>
---
 drivers/tty/serial/omap-serial.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 130f7f8..4def6c3 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c

@@ -1480,6 +1480,10 @@ do_release_region:
 static int serial_omap_remove(struct platform_device *dev)
 {
 	struct uart_omap_port *up = platform_get_drvdata(dev);
+	struct resource		*r;
+
+	r = platform_get_resource(dev, IORESOURCE_MEM, 0);
+	release_mem_region(r->start, resource_size(r));
 
 	if (up) {
 		iounmap(up->port.membase);

-- 
1.7.1