CMP0040: Clarify policy warning to match documentation

In commit v3.5.0-rc1~8^2~2 (Help: Clarify policy `CMP0040`
documentation, 2016-01-28) the documentation was clarified to indicate
that the target must be defined in the current directory.  Do the same
for the text of the policy warning itself.

Fixes: #17399

1 files changed, 1 insertions, 1 deletions

diff --git a/Help/policy/CMP0040.rst b/Help/policy/CMP0040.rst
index d46baf6..0afe589 100644
--- a/Help/policy/CMP0040.rst
+++ b/Help/policy/CMP0040.rst
@@ -2,7 +2,7 @@ CMP0040
 -------
 
 The target in the ``TARGET`` signature of :command:`add_custom_command`
-must exist and must be defined in current directory.
+must exist and must be defined in the current directory.
 
 CMake 2.8.12 and lower silently ignored a custom command created with
 the ``TARGET`` signature of :command:`add_custom_command`