[magma] Remove devfs use

Use services instead of devfs.

Change-Id: I4648bcdf525a6e51cc5be6303f8be3a280fee04d
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/github.com/ARM-software/HWCPipe/+/1360271
Reviewed-by: Craig Stout <cstout@google.com>

vendor/arm/mali/mali_profiler_magma.cpp

diff --git a/vendor/arm/mali/mali_profiler_magma.cpp b/vendor/arm/mali/mali_profiler_magma.cpp
index 5b85ef6..360f32f 100644
--- a/vendor/arm/mali/mali_profiler_magma.cpp
+++ b/vendor/arm/mali/mali_profiler_magma.cpp
@@ -229,7 +229,7 @@
 void MaliProfilerMagma::init()
 {
 	MaliHWInfo hw_info;
-	for (auto &p : std::filesystem::directory_iterator("/dev/class/gpu"))
+	for (auto &p : std::filesystem::directory_iterator("/svc/fuchsia.gpu.magma.Service/"))
 	{
 		zx::channel server_end, client_end;
 		zx_status_t zx_status = zx::channel::create(0, &server_end, &client_end);
@@ -237,7 +237,8 @@
 		{
 			throw std::runtime_error("Failed to create zx channel");
 		}
-		zx_status = fdio_service_connect(p.path().c_str(), server_end.release());
+		std::string path = std::string(p.path().c_str()) + "/device";
+		zx_status = fdio_service_connect(path.c_str(), server_end.release());
 		if (zx_status != ZX_OK)
 		{
 			throw std::runtime_error("Failed to connect to device");
@@ -306,12 +307,13 @@
 	}
 
 	bool success = false;
-	for (auto &p : std::filesystem::directory_iterator("/dev/class/gpu-performance-counters"))
+	for (auto &p : std::filesystem::directory_iterator("/svc/fuchsia.gpu.magma.PerformanceCounterService/"))
 	{
 		zx::channel server_end, client_end;
 		zx::channel::create(0, &server_end, &client_end);
 
-		zx_status_t zx_status = fdio_service_connect(p.path().c_str(), server_end.release());
+		std::string path = std::string(p.path().c_str()) + "/access";
+		zx_status_t zx_status = fdio_service_connect(path.c_str(), server_end.release());
 		if (zx_status != ZX_OK)
 		{
 			throw std::runtime_error("Failed to connect to GPU perf count access service\n");