QuRT: Changes to enable qurt target to build

QuRT doesn't support unlink and does not provide getpid().
The DSPAL layer provides access to usleep so an implementation is
no longer needed.

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

src/platforms/qurt/px4_layer/px4_qurt_impl.cpp

@@ -48,7 +48,6 @@
 #include <errno.h>
 #include <unistd.h>
 #include <semaphore.h>
-#include <qurt.h>
 #include "systemlib/param/param.h"
 
 
@@ -57,14 +56,10 @@ __BEGIN_DECLS
 // FIXME - sysconf(_SC_CLK_TCK) not supported
 long PX4_TICKS_PER_SEC = 1000;
 
-void usleep(useconds_t usec) {
-	qurt_timer_sleep(usec);
-}
-
 unsigned int sleep(unsigned int sec) 
 { 
 	for (unsigned int i=0; i< sec; i++)
-		qurt_timer_sleep(1000000);
+		usleep(1000000);
 	return 0; 
 }
 

src/platforms/qurt/px4_layer/px4_qurt_tasks.cpp

@@ -245,6 +245,20 @@ int px4_task_kill(px4_task_t id, int sig)
 	return rv;
 }
 
+pid_t px4_getpid()
+{
+	pthread_t pid = pthread_self();
+
+	// Get pthread ID from the opaque ID
+	for (int i=0; i<PX4_MAX_TASKS; ++i) {
+		if (taskmap[i].pid == pid) {
+			return i;
+		}
+	}
+	PX4_ERR("px4_getpid() called from non-thread context!");
+	return -EINVAL;
+}
+
 void px4_show_tasks()
 {
 	int idx;