Rust: Use nehalem cpu-target when building with sandybridge arch variant

On Android, sandybridge doesn't include AVX support, so it's more like
nehalem target on Rust toolchain or GCC.

Change-Id: I281e8f5a91271241c48336021582a42acc6d0120
Signed-off-by: hmtheboy154 <buingoc67@gmail.com>
diff --git a/rust/config/x86_64_device.go b/rust/config/x86_64_device.go
index fee1923..540e7fe 100644
--- a/rust/config/x86_64_device.go
+++ b/rust/config/x86_64_device.go
@@ -35,7 +35,7 @@
 		"goldmont-without-sha-xsaves": []string{"-C target-cpu=goldmont", "-C target-feature=-sha,-xsaves"},
 		"haswell":                     []string{"-C target-cpu=haswell"},
 		"ivybridge":                   []string{"-C target-cpu=ivybridge"},
-		"sandybridge":                 []string{"-C target-cpu=sandybridge"},
+		"sandybridge":                 []string{"-C target-cpu=nehalem"},
 		"silvermont":                  []string{"-C target-cpu=silvermont"},
 		"skylake":                     []string{"-C target-cpu=skylake"},
 		//TODO: Add target-cpu=stoneyridge when rustc supports it.
diff --git a/rust/config/x86_device.go b/rust/config/x86_device.go
index 5d9d88a..173950c 100644
--- a/rust/config/x86_device.go
+++ b/rust/config/x86_device.go
@@ -34,7 +34,7 @@
 		"goldmont-without-sha-xsaves": []string{"-C target-cpu=goldmont", "-C target-feature=-sha,-xsaves"},
 		"haswell":                     []string{"-C target-cpu=haswell"},
 		"ivybridge":                   []string{"-C target-cpu=ivybridge"},
-		"sandybridge":                 []string{"-C target-cpu=sandybridge"},
+		"sandybridge":                 []string{"-C target-cpu=nehalem"},
 		"silvermont":                  []string{"-C target-cpu=silvermont"},
 		"skylake":                     []string{"-C target-cpu=skylake"},
 		//TODO: Add target-cpu=stoneyridge when rustc supports it.