hghave: clarify `sqlite` requirements

We need more than the python module, we also need the sqlite3 command line.

Differential Revision: https://phab.mercurial-scm.org/D9787

tests/hghave.py

@@ -1006,7 +1006,7 b' def has_repofncache():'
     return 'fncache' in getrepofeatures()
 
 
-@check('sqlite', 'sqlite3 module is available')
+@check('sqlite', 'sqlite3 module and matching cli is available')
 def has_sqlite():
     try:
         import sqlite3