Ruby » Ruby master

Workaround for OpenBSD make

• common.mk: read from node.h in the source directly, without
  VPATH. [ruby-core:89151] [Bug #15154]

From: kernigh (George Koehler) xkernigh@netscape.net

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66423 b2dd03c8-39d4-4d8f-98ff-823fe69b080e