Typo

cmake/modules/CheckSubmodule.cmake

@@ -4,8 +4,9 @@
 # Looks for a relative file inside source directory of current target
 # - Attempts to clone with git if it's missing
 # - Throws FATAL_ERROR by default unless OPTIONAL is specified
-# - If submodule "foo" is located inside "src/3rdparty/foo", the RELATIVE_FILE
-#   should be foo/file.c, resolving to src/3rdparty/foo/foo/bar.c
+# - If submodule "foo" is located inside "src/3rdparty/foo"
+#   - RELATIVE_FILE: foo/bar.c
+#   - resolving to:  /src/3rdparty/foo/foo/bar.c
 #
 # Usage:
 #       CHECK_SUBMODULE(foo/bar.c)