Fix botched docstring

src/include-bash/sfpi.sh

@@ -159,9 +159,8 @@ sfpi__is_compat() {
     # True if plugin $1 is compatible
     #
     # Load plugin in subshell and look for compatibility function.  If
-    # such function exists, it's called without arguments and 
-    # just to call its compatibility function
-    # and let it decide if it's compatible with this environment.
+    # such function exists, it's called without arguments and if exit
+    # status is zero, plugin is compatible.
     #
     # If plugin has no compatibility function, it's considered
     # compatible.