patch 8.2.4414: solidity files are not recognized

Problem:    Solidity files are not recognized.
Solution:   Add the *.sol pattern. (Dundar Goc, closes #9792)

src/testdir/test_filetype.vim

@@ -480,6 +480,7 @@ let s:filename_checks = {
     \ 'skill': ['file.il', 'file.ils', 'file.cdf'],
     \ 'slang': ['file.sl'],
     \ 'slice': ['file.ice'],
+    \ 'solidity': ['file.sol'],
     \ 'solution': ['file.sln'],
     \ 'slpconf': ['/etc/slp.conf', 'any/etc/slp.conf'],
     \ 'slpreg': ['/etc/slp.reg', 'any/etc/slp.reg'],

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    4414,
 /**/
     4413,
 /**/