[gdb/testsuite] Add -q to INTERNAL_GDBFLAGS

Whenever we start gdb in the testsuite, we have the rather verbose:
...
$ gdb
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(gdb)
...

This makes gdb.log longer than necessary and harder to read.

We do need to test that the output is produced, but that should be limited to
one or a few test-cases.

Fix this by adding -q to INTERNAL_GDBFLAGS, such that we simply have:
...
$ gdb -q
(gdb)
...

Tested on x86_64-linux.

1 files changed, 4 insertions, 1 deletions

diff --git a/gdb/testsuite/gdb.gdb/selftest.exp b/gdb/testsuite/gdb.gdb/selftest.exp
index ac3f3fc..23d180a 100644
--- a/gdb/testsuite/gdb.gdb/selftest.exp
+++ b/gdb/testsuite/gdb.gdb/selftest.exp
@@ -165,4 +165,7 @@ proc test_with_self { } {
     return 0
 }
 
-do_self_tests captured_main test_with_self
+save_vars { INTERNAL_GDBFLAGS } {
+    set INTERNAL_GDBFLAGS [string map {"-q" ""} $INTERNAL_GDBFLAGS]
+    do_self_tests captured_main test_with_self
+}