BuildSystem: Move all userpace libraries under the userspace directory

As the number of libraries is increasing, root directory starts to
expand. This adds better organization for libraries

userspace/libraries/LibC/math.cpp

@@ -0,0 +1,63 @@
+#include <math.h>
+
+#define BUILTINS1(func) \
+	float func##f(float a) { return __builtin_##func##f(a); } \
+	double func(double a) { return __builtin_##func(a); } \
+	long double func##l(long double a) { return __builtin_##func##l(a); }
+
+#define BUILTINS2(func) \
+	float func##f(float a, float b) { return __builtin_##func##f(a, b); } \
+	double func(double a, double b) { return __builtin_##func(a, b); } \
+	long double func##l(long double a, long double b) { return __builtin_##func##l(a, b); } \
+
+__BEGIN_DECLS
+
+BUILTINS1(acos)
+BUILTINS1(acosh)
+BUILTINS1(asin)
+BUILTINS1(asinh)
+BUILTINS1(atan)
+BUILTINS2(atan2)
+BUILTINS1(atanh)
+BUILTINS1(cbrt)
+BUILTINS1(ceil)
+BUILTINS2(copysign)
+BUILTINS1(cos)
+BUILTINS1(cosh)
+BUILTINS1(erf)
+BUILTINS1(erfc)
+BUILTINS1(exp)
+BUILTINS1(exp2)
+BUILTINS1(expm1)
+BUILTINS1(fabs)
+BUILTINS2(fdim)
+BUILTINS1(floor)
+BUILTINS2(fmax)
+BUILTINS2(fmin)
+BUILTINS2(fmod)
+BUILTINS2(hypot)
+BUILTINS1(j0)
+BUILTINS1(j1)
+BUILTINS1(lgamma)
+BUILTINS1(log)
+BUILTINS1(log10)
+BUILTINS1(log1p)
+BUILTINS1(log2)
+BUILTINS1(logb)
+BUILTINS1(nearbyint)
+BUILTINS2(nextafter)
+BUILTINS2(pow)
+BUILTINS2(remainder)
+BUILTINS1(rint)
+BUILTINS1(round)
+BUILTINS1(sin)
+BUILTINS1(sinh)
+BUILTINS1(sqrt)
+BUILTINS1(tan)
+BUILTINS1(tanh)
+BUILTINS1(tgamma)
+BUILTINS1(trunc)
+BUILTINS1(y0)
+BUILTINS1(y1)
+
+__END_DECLS