nova: increase default capability selector count

The reference count get increase to use 2 bytes, so we need the double amount
of selectors as before.

Additionally print a message if we run out of capabilities in a server. Since
our rpc framework is now clever enough to detect that for a printf we don't
need to setup a receive window, we may use a printf instead of a die call.
Eases debugging.

Issue #1601

repos/base-nova/src/base/server/server.cc

@@ -159,10 +159,8 @@ void Rpc_entrypoint::_activation_entry()
 		tmp->release();
 	}
 
-	/* if we can't setup receive window, die in order to recognize the issue */
 	if (!ep->_rcv_buf.prepare_rcv_window((Nova::Utcb *)ep->utcb()))
-		/* printf doesn't work here since for IPC also prepare_rcv_window is used */
-		nova_die();
+		PWRN("out of capability selectors for handling server requests");
 
 	srv << IPC_REPLY;
 }

repos/base-nova/src/base/thread/thread_context.cc

@@ -77,7 +77,7 @@ void prepare_init_main_thread()
 	/* for Core we can't perform the following code so early */
 	if (!__initial_sp) {
 
-		enum { CAP_RANGES = 16 };
+		enum { CAP_RANGES = 32 };
 
 		unsigned index = initial_cap_range()->base() +
 		                 initial_cap_range()->elements();

repos/base-nova/src/core/platform.cc

@@ -627,7 +627,7 @@ Platform::Platform() :
 
 	/* add capability selector ranges to map */
 	unsigned index = 0x2000;
-	for (unsigned i = 0; i < 16; i++)
+	for (unsigned i = 0; i < 32; i++)
 	{
 		void * phys_ptr = 0;
 		ram_alloc()->alloc(4096, &phys_ptr);