AP_Math: benchmarks: define hal

libraries/AP_Math/benchmarks/benchmark_geodesic_grid.cpp

@@ -18,6 +18,8 @@
 
 #include <AP_Math/AP_GeodesicGrid.h>
 
+const AP_HAL::HAL& hal = AP_HAL::get_HAL();
+
 static const Vector3f triangles[20][3] = {
     {{-M_GOLDEN, 1, 0}, {-1, 0,-M_GOLDEN}, {-M_GOLDEN,-1, 0}},
     {{-1, 0,-M_GOLDEN}, {-M_GOLDEN,-1, 0}, { 0,-M_GOLDEN,-1}},

libraries/AP_Math/benchmarks/benchmark_matrix.cpp

@@ -2,6 +2,8 @@
 
 #include <AP_Math/AP_Math.h>
 
+const AP_HAL::HAL& hal = AP_HAL::get_HAL();
+
 static void BM_MatrixMultiplication(benchmark::State& state)
 {
     Matrix3f m1(Vector3f(1.0f, 2.0f, 3.0f),