chcon: added implementation and integration tests

The ToDo list was updated to mark `chcon` as done.

Building and testing `chcon` requires enabling the `feat_selinux` feature. If `make` is used for building, then please specify `SELINUX_ENABLED=1` if building and testing on a system where SELinux is not enabled.

.vscode/cspell.dictionaries/shell.wordlist.txt

@@ -63,6 +63,7 @@ abspath
 addprefix
 addsuffix
 endef
+findstring
 firstword
 ifeq
 ifneq
@@ -89,5 +90,9 @@ markdownlint
 rerast
 rollup
 sed
+selinuxenabled
 wslpath
 xargs
+
+# * directories
+sbin

.vscode/cspell.dictionaries/workspace.wordlist.txt

@@ -106,6 +106,7 @@ whoami
 # * vars/errno
 errno
 EEXIST
+ENODATA
 ENOENT
 ENOSYS
 EPERM
@@ -118,7 +119,9 @@ fcntl
 vmsplice
 
 # * vars/libc
+COMFOLLOW
 FILENO
+FTSENT
 HOSTSIZE
 IDSIZE
 IFBLK
@@ -151,6 +154,7 @@ SIGTERM
 SYS_fdatasync
 SYS_syncfs
 USERSIZE
+accpath
 addrinfo
 addrlen
 blocksize
@@ -174,15 +178,18 @@ inode
 inodes
 isatty
 lchown
+pathlen
 setgid
 setgroups
 settime
 setuid
 socktype
 statfs
+statp
 statvfs
 strcmp
 strerror
+strlen
 syncfs
 umask
 waitpid
@@ -274,6 +281,13 @@ winerror
 winnt
 winsock
 
+# * vars/selinux
+freecon
+getfilecon
+lgetfilecon
+lsetfilecon
+setfilecon
+
 # * vars/uucore
 optflag
 optflagmulti