Add impl From<f16> for f32

Author: beetrees

library/core/src/convert/num.rs

@@ -174,6 +174,7 @@ impl_from!(u64 => f128, #[unstable(feature = "f128", issue = "116909")], #[unsta
 // float -> float
 // FIXME(f16,f128): adding additional `From<{float}>` impls to `f32` breaks inference. See
 // <https://github.com/rust-lang/rust/issues/123831>
+impl_from!(f16 => f32, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
 impl_from!(f16 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
 impl_from!(f16 => f128, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);
 impl_from!(f32 => f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")]);