optimize aarch64 when able (#10433)

# Description

This PR optimizes for the aarch64 m1 processor when able.

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.cargo/config.toml

@@ -26,3 +26,8 @@ rustflags = ["-C", "link-args=-stack:10000000", "-C", "target-feature=+crt-stati
 # [target.aarch64-apple-darwin]
 # linker = "clang"
 # rustflags = ["-C", "link-arg=-fuse-ld=mold"]
+
+[target.aarch64-apple-darwin]
+# We can guarantee that this target will always run on a CPU with _at least_
+# these capabilities, so let's optimize for them
+rustflags = ["-Ctarget-cpu=apple-m1"]