Fix the following clang warning:
gcc/spellcheck.c:477:3: warning: suspicious concatenation of string literals in an array initialization;
did you mean to separate the elements with a comma? [-Wstring-concatenation]
gcc/ChangeLog:
* spellcheck.c: Add missing comma in initialization.
"foo",
"food",
"boo",
- "1234567890123456789012345678901234567890123456789012345678901234567890"
+ "1234567890123456789012345678901234567890123456789012345678901234567890",
"abc",
"ac",
"ca",