Move nacl_helper_linux.cc to components/nacl
    
Move the NaCl linux helper into the components/nacl/loader directory as well
as the build target to components/nacl.gyp. This patch also
removed chrome/nacl.gypi which is not needed anymore.
    
This is part of an effort to componentize NaCl code.
    
Patch by mrunal.kapade@intel.com with modifications by myself.

BUG=244791

Review URL: https://codereview.chromium.org/58333002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@234379 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 234379