[target/msm7627]: Fix size mismatch for recovery mode

Increase the size of BOOT_MODE field for msm7627_surf and msm7627_ffa
targets from 4 bytes to 8 bytes to match with the size present in shared memory.
diff --git a/target/msm7627_surf/init.c b/target/msm7627_surf/init.c
index a860e07..f8c2fb3 100644
--- a/target/msm7627_surf/init.c
+++ b/target/msm7627_surf/init.c
@@ -133,7 +133,7 @@
 
 unsigned check_reboot_mode(void)
 {
-    unsigned mode = 0;
+    unsigned mode[2] = {0, 0};
     unsigned int mode_len = sizeof(mode);
     unsigned smem_status;
 
@@ -144,5 +144,5 @@
       dprintf(CRITICAL, "ERROR: unable to read shared memory for reboot mode\n");
       return 0;
     }
-    return mode;
+    return mode[0];
 }