cephfs-shell: move source to separate subdirectory

This ensures the package discovery done by python setuptools >= 61
doesn't get confused when building cephfs-shell and cephfs-top.
This commit moves cephfs-shell to a separate "shell" subdirectory,
which is the same approach we've already got with the cephfs-top
tool being in a separate "top" subdirectory.

Fixes: https://tracker.ceph.com/issues/56658
Signed-off-by: Tim Serong <tserong@suse.com>

src/tools/cephfs/CMakeLists.txt

@@ -49,12 +49,7 @@ install(TARGETS
 
 option(WITH_CEPHFS_SHELL "install cephfs-shell" OFF)
 if(WITH_CEPHFS_SHELL)
-  include(Distutils)
-  distutils_install_module(cephfs-shell)
-  if(WITH_TESTS)
-    include(AddCephTest)
-    add_tox_test(cephfs-shell)
-  endif()
+  add_subdirectory(shell)
 endif()
 
 option(WITH_CEPHFS_TOP "install cephfs-top utility" ON)

src/tools/cephfs/shell/CMakeLists.txt

@@ -0,0 +1,7 @@
+include(Distutils)
+distutils_install_module(cephfs-shell)
+
+if(WITH_TESTS)
+  include(AddCephTest)
+  add_tox_test(cephfs-shell)
+endif()