Help: Fix up the VISIBILITY_INLINES_HIDDEN docs.

Resolve some sentence fragments, remove a copy-pasto from other docs
and use a link to the CMAKE_VISIBILITY_INLINES_HIDDEN variable.

Help/prop_tgt/VISIBILITY_INLINES_HIDDEN.rst

@@ -4,8 +4,8 @@ VISIBILITY_INLINES_HIDDEN
 Whether to add a compile flag to hide symbols of inline functions
 
 The VISIBILITY_INLINES_HIDDEN property determines whether a flag for
-hiding symbols for inline functions.  the value passed used in a
-visibility related compile option, such as -fvisibility=.  This
-property only has an affect for libraries and executables with
-exports.  This property is initialized by the value of the variable
-CMAKE_VISIBILITY_INLINES_HIDDEN if it is set when a target is created.
+hiding symbols for inline functions, such as -fvisibility-inlines-hidden,
+should be used when invoking the compiler.  This property only has an affect
+for libraries and executables with exports.  This property is initialized by
+the value of the :variable:`CMAKE_VISIBILITY_INLINES_HIDDEN` if it is set
+when a target is created.