patch 9.0.1381: ACCESS_ names have a conflict with on some systems

Problem:    ACCESS_ names have a conflict with on some systems.
Solution:   Rename by prepending VIM_. (Ola Söder, closes #12105)
diff --git a/src/eval.c b/src/eval.c
index 0d32fa0..a647b51 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -1576,11 +1576,11 @@
 			{
 			    switch (om->ocm_access)
 			    {
-				case ACCESS_PRIVATE:
+				case VIM_ACCESS_PRIVATE:
 					semsg(_(e_cannot_access_private_member_str),
 								 om->ocm_name);
 					return NULL;
-				case ACCESS_READ:
+				case VIM_ACCESS_READ:
 					if ((flags & GLV_READ_ONLY) == 0)
 					{
 					    semsg(_(e_member_is_not_writable_str),
@@ -1588,7 +1588,7 @@
 					    return NULL;
 					}
 					break;
-				case ACCESS_ALL:
+				case VIM_ACCESS_ALL:
 					break;
 			    }