arch-arm: Fix inverted 32/64-bit check in GDB

Change-Id: Ided438af19c9b8504d4624119c4d9fb5157c7cf0
Reviewed-on: https://gem5-review.googlesource.com/4720
Reviewed-by: Paul Rosenfeld <prosenfeld@micron.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

src/arch/arm/remote_gdb.cc

@@ -305,7 +305,7 @@ RemoteGDB::BaseGdbRegCache*
 RemoteGDB::gdbRegs()
 {
     if (inAArch64(context))
-        return &regCache32;
-    else
         return &regCache64;
+    else
+        return &regCache32;
 }