patch 9.1.0783: 'spell' option setting has problems

Problem:  'spell' option setting has problems
Solution: correctly check for comma for 'spellfile' option,
          remove unnecessary checks, refactor slightly (Milly)

closes: #15873

Signed-off-by: Milly <milly.ca@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/option.c b/src/option.c
index cdd457b..a108c52 100644
--- a/src/option.c
+++ b/src/option.c
@@ -2956,7 +2956,7 @@
     (void)spell_check_msm();
     (void)spell_check_sps();
     (void)compile_cap_prog(curwin->w_s);
-    (void)did_set_spell_option(TRUE);
+    (void)did_set_spell_option();
 #endif
     // set cedit_key
     (void)did_set_cedit(NULL);