Canonicalize the path used by sh.

With a bunch of LibC work to support the feature. LibC now initializes
AK::StringImpl by default. It's now fine to use AK in LibC/Userland! :^)

LibC/entry.cpp

@@ -1,4 +1,5 @@
 #include <Kernel/Syscall.h>
+#include <AK/StringImpl.h>
 
 extern "C" int main(int, char**);
 
@@ -8,6 +9,8 @@ extern "C" int _start()
 {
     errno = 0;
 
+    StringImpl::initializeGlobals();
+
     int argc;
     char** argv;
     int rc = Syscall::invoke(Syscall::GetArguments, (dword)&argc, (dword)&argv);