uefi-std: Drop sqrt

sqrt is available through compiler-builtins 0.1.77 and newer.

Fixes compiling system76-firmware-update with latest toolchain.

Ref: rust-lang/compiler-builtins#480
Signed-off-by: Tim Crawford <[email protected]>

Author: crawfxrd

crates/uefi_std/src/rt/math.rs

@@ -1,3 +1,2 @@
-pub mod math;
 pub mod panic;
 pub mod start;