Multiple by itself instead of std::pow

Co-authored-by: Even Rouault <[email protected]>

alg/los.cpp

@@ -210,7 +210,7 @@ bool GDALIsLineOfSightVisible(const GDALRasterBandH hBand, const int xA,
     // Use an interpolated Z height with 2D bresenham for the remaining cases.
 
     // Lambda for computing the square of a number
-    auto SQUARE = [](const int n) -> int { return std::pow(n, 2); };
+    auto SQUARE = [](const int n) -> int { return n * n ; };
 
     // Lambda for Linear interpolate like C++20 std::lerp.
     auto lerp = [](const double a, const double b, const double t)