[HIPIFY][FIX][#306] Eliminate second cuda main include directive

// hipified to #include<hip/hip_runtime.h>
#include<cuda.h> // 1st cuda main include (Driver API)
// to eliminate
#include<cuda_runtime.h> // 2nd cuda main include (Runtime API)

HIP has one header hip_runtime.h for both CUDA APIs, thus second cuda main include directive is eliminated entirely.

tests/hipify-clang/headers_test_01.cu

@@ -0,0 +1,6 @@
+// RUN: %run_test hipify "%s" "%t" %cuda_args
+
+// CHECK: #include <hip/hip_runtime.h>
+#include <cuda.h>
+// CHECK-NOT: #include<cuda_runtime.h>
+#include <cuda_runtime.h>

tests/hipify-clang/headers_test_02.cu

@@ -0,0 +1,6 @@
+// RUN: %run_test hipify "%s" "%t" %cuda_args
+
+// CHECK: #include <hip/hip_runtime.h>
+#include <cuda_runtime.h>
+// CHECK-NOT: #include<cuda.h>
+#include <cuda.h>