Remove workaround for cortex-a55/a75

Test: m checkbuild
Test: boot on a55/a75 device, pass bionic tests
Bug: 110235326
Change-Id: I5ab2102352a6efe1173b3097875e6e779d4a1a09
diff --git a/cc/config/arm64_device.go b/cc/config/arm64_device.go
index 73cee5c..172784a 100644
--- a/cc/config/arm64_device.go
+++ b/cc/config/arm64_device.go
@@ -53,15 +53,12 @@
 			"-mcpu=cortex-a53",
 		},
 		"cortex-a55": []string{
-			// The cortex-a55 target is not yet supported,
-			// so use cortex-a53.
-			"-mcpu=cortex-a53",
+			"-mcpu=cortex-a55",
 		},
 		"cortex-a75": []string{
-			// Use the cortex-a53 since it is similar to the little
+			// Use the cortex-a55 since it is similar to the little
 			// core (cortex-a55) and is sensitive to ordering.
-			// The cortex-a55 target is not yet supported.
-			"-mcpu=cortex-a53",
+			"-mcpu=cortex-a55",
 		},
 		"kryo": []string{
 			// Use the cortex-a57 cpu since some compilers