patch 9.0.1176: smithy files are not recognized

Problem:    smithy files are not recognized.
Solution:   Add a pattern for Smithy files. (Chris Kipp, closes #11804)

src/testdir/test_filetype.vim

@@ -528,6 +528,7 @@ let s:filename_checks = {
     \ 'smarty': ['file.tpl'],
     \ 'smcl': ['file.hlp', 'file.ihlp', 'file.smcl'],
     \ 'smith': ['file.smt', 'file.smith'],
+    \ 'smithy': ['file.smithy'],
     \ 'sml': ['file.sml'],
     \ 'snobol4': ['file.sno', 'file.spt'],
     \ 'solidity': ['file.sol'],

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1176,
 /**/
     1175,
 /**/