AK+Everywhere: Rename String to DeprecatedString

We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)

Userland/Libraries/LibGPU/Driver.cpp

@@ -4,8 +4,8 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/DeprecatedString.h>
 #include <AK/HashMap.h>
-#include <AK/String.h>
 #include <AK/WeakPtr.h>
 #include <LibGPU/Driver.h>
 #include <dlfcn.h>
@@ -13,7 +13,7 @@
 namespace GPU {
 
 // FIXME: Think of a better way to configure these paths. Maybe use ConfigServer?
-static HashMap<String, String> const s_driver_path_map
+static HashMap<DeprecatedString, DeprecatedString> const s_driver_path_map
 {
 #if defined(AK_OS_SERENITY)
     { "softgpu", "libsoftgpu.so.serenity" },
@@ -24,7 +24,7 @@ static HashMap<String, String> const s_driver_path_map
 #endif
 };
 
-static HashMap<String, WeakPtr<Driver>> s_loaded_drivers;
+static HashMap<DeprecatedString, WeakPtr<Driver>> s_loaded_drivers;
 
 ErrorOr<NonnullRefPtr<Driver>> Driver::try_create(StringView driver_name)
 {