Remove macros that the Linux host no longer needs.

We patched our ancient glibc to match current glibc (and bionic/musl).

Test: treehugger
Change-Id: I6377b5dfb94d3a0e2209d4c2f0661ef81d362fc3

cc/config/x86_linux_host.go

@@ -30,11 +30,6 @@ var (
 		"-D_FORTIFY_SOURCE=2",
 		"-fstack-protector",
 
-		// Workaround differences in inttypes.h between host and target.
-		//See bug 12708004.
-		"-D__STDC_FORMAT_MACROS",
-		"-D__STDC_CONSTANT_MACROS",
-
 		"--gcc-toolchain=${LinuxGccRoot}",
 		"-fstack-protector-strong",
 	}