[target/qsd8250]: Fix the macro named used for 512MB RAM support.

Change-Id: I17855af02c9e17065f563831731f51771c010794
diff --git a/target/qsd8250_surf/atags.c b/target/qsd8250_surf/atags.c
index ec80183..77a1fb8 100644
--- a/target/qsd8250_surf/atags.c
+++ b/target/qsd8250_surf/atags.c
@@ -63,7 +63,7 @@
 
 	/* 2nd segment */
 #ifdef USE_512M_RAM
-	size = EBT1_SIZE2_512M;
+	size = EBI1_SIZE2_512M;
 #else
 	size = 0;
 #endif