patch 9.0.1076: ASAN complains about NULL argument

Problem:    ASAN complains about NULL argument.
Solution:   Skip memmove() when there is nothing to move.
diff --git a/src/version.c b/src/version.c
index a734f55..f1a34b5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1076,
+/**/
     1075,
 /**/
     1074,
diff --git a/src/vim9class.c b/src/vim9class.c
index 4a97585..a91a4a5 100644
--- a/src/vim9class.c
+++ b/src/vim9class.c
@@ -164,7 +164,8 @@
     *members = gap->ga_len == 0 ? NULL : ALLOC_MULT(ocmember_T, gap->ga_len);
     if (gap->ga_len > 0 && *members == NULL)
 	return FAIL;
-    mch_memmove(*members, gap->ga_data, sizeof(ocmember_T) * gap->ga_len);
+    if (gap->ga_len > 0)
+	mch_memmove(*members, gap->ga_data, sizeof(ocmember_T) * gap->ga_len);
     VIM_CLEAR(gap->ga_data);
     return OK;
 }