plat: marvell: rename common include file

Rename a8k_common.h to armada_common.h to keep the same header
name across all other Marvell Armada platforms.
This is especially useful since various Marvell platforms may
use common platform files and share the driver modules.

Change-Id: I7262105201123d54ccddef9aad4097518f1e38ef
Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>
diff --git a/drivers/marvell/i2c/a8k_i2c.c b/drivers/marvell/i2c/a8k_i2c.c
index 737dd0a..72a7731 100644
--- a/drivers/marvell/i2c/a8k_i2c.c
+++ b/drivers/marvell/i2c/a8k_i2c.c
@@ -442,7 +442,7 @@
 void i2c_init(void *i2c_base)
 {
 	/* For I2C speed and slave address, now we do not set them since
-	 * we just provide the working speed and slave address in plat_def.h
+	 * we just provide the working speed and slave address in mvebu_def.h
 	 * for i2c_init
 	 */
 	base = (struct marvell_i2c_regs *)i2c_base;