Set GDB version number to 17.1.

This commit changes gdb/version.in to 17.1.

gdb/version.in

diff --git a/gdb/version.in b/gdb/version.in
index 742cf5d..641f838 100644
--- a/gdb/version.in
+++ b/gdb/version.in
@@ -1 +1 @@
-17.0.90.DATE-git
+17.1