maint: style: initialize some struct members

[Akim Demaille]

commit f99c8ca3712cbe04e316b32a1fa5742fd462e2bb
Author: Akim Demaille <address@hidden>
Date:   Sun Mar 8 07:18:34 2020 +0100

    style: initialize some struct members
    
    * src/symtab.c (sym_content_new): Initialize all the location members.
    Not needed by the code, but disturbing values when using a debugger.

diff --git a/src/symtab.c b/src/symtab.c
index 35c0930e..b137bbf0 100644
--- a/src/symtab.c
+++ b/src/symtab.c
@@ -77,10 +77,12 @@ sym_content_new (symbol *s)
   res->symbol = s;
 
   res->type_name = NULL;
+  res->type_loc = empty_loc;
   for (int i = 0; i < CODE_PROPS_SIZE; ++i)
     code_props_none_init (&res->props[i]);
 
   res->number = NUMBER_UNDEFINED;
+  res->prec_loc = empty_loc;
   res->prec = 0;
   res->assoc = undef_assoc;
   res->user_token_number = USER_NUMBER_UNDEFINED;