patman: Update the run script

Patman now has its main program in a function, so update the toml file
to match.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/patman/pyproject.toml b/tools/patman/pyproject.toml
index f29516a..5613194 100644
--- a/tools/patman/pyproject.toml
+++ b/tools/patman/pyproject.toml
@@ -23,7 +23,7 @@
 "Bug Tracker" = "https://source.denx.de/groups/u-boot/-/issues"
 
 [project.scripts]
-patman = "patman.__main__"
+patman = "patman.__main__:run_patman"
 
 [tool.setuptools.package-data]
 patman = ["*.rst"]