dev-cpp/ms-gsl: keyword on ~ppc64

Test project /var/tmp/portage/dev-cpp/ms-gsl-2.0.0/work/ms-gsl-2.0.0_build
      Start  1: span_tests
      Start  2: multi_span_tests
      Start  3: strided_span_tests
      Start  4: string_span_tests
      Start  5: at_tests
      Start  6: bounds_tests
      Start  7: notnull_tests
      Start  8: assertion_tests
      Start  9: utils_tests
      Start 10: owner_tests
      Start 11: byte_tests
      Start 12: algorithm_tests
      Start 13: sloppy_notnull_tests
      Start 14: no_exception_throw_tests
      Start 15: no_exception_ensure_tests
 1/15 Test  #1: span_tests .......................   Passed    0.10 sec
 2/15 Test  #2: multi_span_tests .................   Passed    0.09 sec
 3/15 Test  #3: strided_span_tests ...............   Passed    0.09 sec
 4/15 Test  #4: string_span_tests ................   Passed    0.08 sec
 5/15 Test  #5: at_tests .........................   Passed    0.07 sec
 6/15 Test  #6: bounds_tests .....................   Passed    0.07 sec
 7/15 Test  #7: notnull_tests ....................   Passed    0.06 sec
 8/15 Test  #8: assertion_tests ..................   Passed    0.05 sec
 9/15 Test  #9: utils_tests ......................   Passed    0.05 sec
10/15 Test #10: owner_tests ......................   Passed    0.04 sec
11/15 Test #11: byte_tests .......................   Passed    0.04 sec
12/15 Test #12: algorithm_tests ..................   Passed    0.03 sec
13/15 Test #13: sloppy_notnull_tests .............   Passed    0.02 sec
14/15 Test #14: no_exception_throw_tests .........   Passed    0.02 sec
15/15 Test #15: no_exception_ensure_tests ........   Passed    0.01 sec

100% tests passed, 0 tests failed out of 15

Package-Manager: Portage-2.3.87, Repoman-2.3.20
Signed-off-by: Georgy Yakovlev <gyakovlev@gentoo.org>

dev-cpp/ms-gsl/ms-gsl-2.0.0.ebuild

@@ -1,4 +1,4 @@
-# Copyright 1999-2019 Gentoo Authors
+# Copyright 1999-2020 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 EAPI=6
@@ -13,7 +13,7 @@ S="${WORKDIR}/GSL-${PV}"
 
 LICENSE="MIT"
 SLOT="0"
-KEYWORDS="amd64 x86"
+KEYWORDS="amd64 ~ppc64 x86"
 IUSE="test"
 RESTRICT="!test? ( test )"