Parenthesize frame.h macro definitions

Parenthesize frame.h macro definitions

* src/frame.h (FRAME_TOOL_BAR_POSITION)
(FRAME_VERTICAL_SCROLL_BAR_TYPE, FRAME_HAS_VERTICAL_SCROLL_BARS)
(FRAME_HAS_VERTICAL_SCROLL_BARS_ON_LEFT)
(FRAME_HAS_VERTICAL_SCROLL_BARS_ON_RIGHT)
(FRAME_OVERRIDE_REDIRECT, FRAME_UNDECORATED, FRAME_PARENT_FRAME)
(FRAME_SKIP_TASKBAR, FRAME_NO_FOCUS_ON_MAP)
(FRAME_NO_ACCEPT_FOCUS, FRAME_NO_SPECIAL_GLYPHS, FRAME_Z_GROUP)
(FRAME_Z_GROUP_NONE, FRAME_Z_GROUP_ABOVE, FRAME_Z_GROUP_BELOW)
(FRAME_HAS_HORIZONTAL_SCROLL_BARS): Parenthesize macro definiens
to allow arbitrary expression arguments.