patch 8.1.1911: more functions can be used as methods

Problem:    More functions can be used as methods.
Solution:   Make a few more functions usable as a method.
diff --git a/src/evalfunc.c b/src/evalfunc.c
index b154840..963c95f 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -466,10 +466,10 @@
     {"bufnr",		1, 2, FEARG_1,	  f_bufnr},
     {"bufwinid",	1, 1, FEARG_1,	  f_bufwinid},
     {"bufwinnr",	1, 1, FEARG_1,	  f_bufwinnr},
-    {"byte2line",	1, 1, 0,	  f_byte2line},
-    {"byteidx",		2, 2, 0,	  f_byteidx},
-    {"byteidxcomp",	2, 2, 0,	  f_byteidxcomp},
-    {"call",		2, 3, 0,	  f_call},
+    {"byte2line",	1, 1, FEARG_1,	  f_byte2line},
+    {"byteidx",		2, 2, FEARG_1,	  f_byteidx},
+    {"byteidxcomp",	2, 2, FEARG_1,	  f_byteidxcomp},
+    {"call",		2, 3, FEARG_1,	  f_call},
 #ifdef FEAT_FLOAT
     {"ceil",		1, 1, FEARG_1,	  f_ceil},
 #endif