ahci: Make ahci_port_base() non-static to enable overwrite

To allow a board- / platform-specific ahci_port_base() function, this
patch removes "static inline" and adds __weak to this function. This
will be used by the upcoming Armada 7K/8K SATA / AHCI support, which
unfortunately needs a different port base address calculation.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Nadav Haklai <nadavh@marvell.com>
Cc: Neta Zur Hershkovits <neta@marvell.com>
Cc: Kostya Porotchkin <kostap@marvell.com>
Cc: Omri Itach <omrii@marvell.com>
Cc: Igal Liberman <igall@marvell.com>
Cc: Haim Boot <hayim@marvell.com>
Cc: Hanna Hawa <hannah@marvell.com>
diff --git a/drivers/block/ahci.c b/drivers/block/ahci.c
index 2e1ddf9..5139989 100644
--- a/drivers/block/ahci.c
+++ b/drivers/block/ahci.c
@@ -45,7 +45,7 @@
 #define WAIT_MS_FLUSH	5000
 #define WAIT_MS_LINKUP	200
 
-static inline void __iomem *ahci_port_base(void __iomem *base, u32 port)
+__weak void __iomem *ahci_port_base(void __iomem *base, u32 port)
 {
 	return base + 0x100 + (port * 0x80);
 }