CrayPE fixes for the slepc package (#23503)

Use the gold linker for CCE (this may change later)

Co-authored-by: Tamara Dahlgren <35777542+tldahlgren@users.noreply.github.com>

var/spack/repos/builtin/packages/slepc/package.py

@@ -95,8 +95,12 @@ def install(self, spec, prefix):
         # its symlink in spack/stage/ !
         os.environ['SLEPC_DIR'] = os.getcwd()
 
-        options = []
+        if self.spec.satisfies('%cce'):
+            filter_file('          flags = l',
+                        '          flags = l\n        flags += ["-fuse-ld=gold"]',
+                        'config/package.py')
 
+        options = []
         if '+arpack' in spec:
             options.extend([
                 '--with-arpack-dir=%s' % spec['arpack-ng'].prefix,