caliper: Fix for aarch64 (#19564)

var/spack/repos/builtin/packages/caliper/for_aarch64.patch

@@ -0,0 +1,11 @@
+--- spack-src/src/services/callpath/Callpath.cpp.bak	2020-10-28 14:38:19.668122844 +0900
++++ spack-src/src/services/callpath/Callpath.cpp	2020-10-28 15:03:12.258061188 +0900
+@@ -63,7 +63,7 @@
+         unw_context_t unw_ctx;
+         unw_cursor_t  unw_cursor;
+ 
+-        unw_getcontext(&unw_ctx);
++        unw_getcontext(unw_ctx);
+ 
+         if (unw_init_local(&unw_cursor, &unw_ctx) < 0) {
+             Log(0).stream() << "callpath: unable to init libunwind cursor" << endl;

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

@@ -79,6 +79,8 @@ class Caliper(CMakePackage):
     conflicts('+dyninst', when='@:1.99',
               msg='Dyninst unsupported by version <=2.0.1')
 
+    patch('for_aarch64.patch', when='target=aarch64:')
+
     def cmake_args(self):
         spec = self.spec