Add explicit default switch branch to avoid too many runtime methods for compilation

Author: msimacek

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/ctypes/CtypesModuleBuiltins.java

@@ -1385,6 +1385,8 @@ static Object callGetFunc(Object restype, FFIType rtype, Object result, Object c
                         }
                         yield pointer.createReference();
                     }
+                    // Needed because javac-generated default is not PE-friendly
+                    default -> throw CompilerDirectives.shouldNotReachHere();
                 };
             } catch (UnsupportedMessageException | InvalidArrayIndexException e) {
                 throw CompilerDirectives.shouldNotReachHere(e);