[pushed] [gdb/testsuite] Fix gdb.base/condbreak-multi-context.exp with gcc 4.8.5

[Tom de Vries <tdevries@suse.de>]

With gcc 4.8.5, I run into:
...
Running gdb.base/condbreak-multi-context.exp ...
gdb compile failed, condbreak-multi-context.cc:21:11: warning: non-static \
  data member initializers only available with -std=c++11 or -std=gnu++11 \
  [enabled by default]
   int b = 20;
           ^
...

Fix this by making it a static const.

Tested on x86_64-linux, with gcc 4.8.5, 7.5.0 and clang 13.0.1.
---
 gdb/testsuite/gdb.base/condbreak-multi-context.cc | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/gdb/testsuite/gdb.base/condbreak-multi-context.cc b/gdb/testsuite/gdb.base/condbreak-multi-context.cc
index 0192478f0d2..914c003b00f 100644
--- a/gdb/testsuite/gdb.base/condbreak-multi-context.cc
+++ b/gdb/testsuite/gdb.base/condbreak-multi-context.cc
@@ -18,7 +18,7 @@
 class Base
 {
 public:
-  int b = 20;
+  static const int b = 20;
 
   void func () {}
 };
@@ -26,7 +26,7 @@ public:
 class A : public Base
 {
 public:
-  int a = 10;
+  static const int a = 10;
 
   void func () {}
 };
@@ -34,7 +34,7 @@ public:
 class C : public Base
 {
 public:
-  int c = 30;
+  static const int c = 30;
 
   void func () {}
 };

base-commit: 9c71ba0dc4f4ad7ab7e5f7711be6e7fde6118a06
-- 
2.35.3