`build: Inherit flags from rustc` causes rustc build failures

[clubby789]

rust-lang/rust#134425 (comment)

Bisected to #1279

Looks like we get something like

/usr/bin/ld: /rustroot/bin/../lib/LLVMgold.so: error loading plugin: /rustroot/bin/../lib/LLVMgold.so: cannot open sha
red object file: No such file or directory

while running tikv-jemalloc-sys's configure, as well as some

Inherited flag "-fembed-bitcode=all" is not supported by the currently used CC

warnings

[workingjubilee]

@mrkajetanp

[clubby789]

Removing the inherited -flto=thin prevents the error.

cc-rs/src/lib.rs

Lines 728 to 729 in 5673a3f

	// Checking for compiler flags does not require linking
	cmd.arg("-c");

This prevents us from reaching the linker and hitting linker errors