Input: use std::lerp instead of lerp template

rpcs3/Emu/Io/PadHandler.h

@@ -321,11 +321,6 @@ protected:
 	std::unordered_map<u32, std::string> button_list;
 	std::vector<u32> blacklist;
 
-	template <typename T>
-	T lerp(T v0, T v1, T t) {
-		return std::fma(t, v1, std::fma(-t, v0, v0));
-	}
-
 	// Search an unordered map for a string value and return found keycode
 	static int FindKeyCode(const std::unordered_map<u32, std::string>& map, const cfg::string& name, bool fallback = true);
 

rpcs3/Input/keyboard_pad_handler.cpp

@@ -693,7 +693,7 @@ void keyboard_pad_handler::ThreadProc()
 						const f32 v1 = static_cast<f32>(m_stick_val[j]);
 
 						// linear interpolation from the current stick value v0 to the desired stick value v1
-						f32 res = lerp(v0, v1, stick_lerp_factor);
+						f32 res = std::lerp(v0, v1, stick_lerp_factor);
 
 						// round to the correct direction to prevent sticky sticks on small factors
 						res = (v0 <= v1) ? std::ceil(res) : std::floor(res);