external/boringssl: Sync to c642aca28feb7e18f244658559f4042286aed0c8.

This includes the following changes:

https://boringssl.googlesource.com/boringssl/+log/14308731e5446a73ac2258688a9688b524483cb6..c642aca28feb7e18f244658559f4042286aed0c8

Test: BoringSSL CTS Presubmits
Change-Id: Ia0b5b2cdd64eb2b54ec5335d48da9001e9d6dafa
diff --git a/src/util/all_tests.go b/src/util/all_tests.go
index 235db05..d3f9203 100644
--- a/src/util/all_tests.go
+++ b/src/util/all_tests.go
@@ -162,7 +162,16 @@
 }
 
 func sdeOf(cpu, path string, args ...string) *exec.Cmd {
-	sdeArgs := []string{"-" + cpu, "--", path}
+	sdeArgs := []string{"-" + cpu}
+	// The kernel's vdso code for gettimeofday sometimes uses the RDTSCP
+	// instruction. Although SDE has a -chip_check_vsyscall flag that
+	// excludes such code by default, it does not seem to work. Instead,
+	// pass the -chip_check_exe_only flag which retains test coverage when
+	// statically linked and excludes the vdso.
+	if cpu == "p4p" || cpu == "pnr" || cpu == "mrm" || cpu == "slt" {
+		sdeArgs = append(sdeArgs, "-chip_check_exe_only")
+	}
+	sdeArgs = append(sdeArgs, "--", path)
 	sdeArgs = append(sdeArgs, args...)
 	return exec.Command(*sdePath, sdeArgs...)
 }