[ARC] Update LINK_EH_SPEC linker spec.

[ARC] Update LINK_EH_SPEC linker spec.

With no trailing space in LINK_EH_SPEC linker spec gets generated as:
------------------------>8---------------------
%{!r:--build-id} --eh-frame-hdr%{h*} ...
------------------------>8---------------------

or even worse if hash style is added:
------------------------>8---------------------
%{!r:--build-id} --eh-frame-hdr--hash-style=sysv %{h*} ...
------------------------>8---------------------

Now if that spec is really used by LD then it fails inevitably
saying that it doesn't know option "--eh-frame-hdr--hash-style=sysv".

2018-09-17  Alexey Brodkin  <abrodkin@synopsys.com>

	* config/arc/linux.h (LINK_EH_SPEC): Add missing space.

From-SVN: r264361