Switch to FreeBSD's actual sincos.

Before:
  BM_math_sin_fast                48 ns         48 ns   14693053
  BM_math_sincos                  61 ns         61 ns   11470219

After:
  BM_math_sin_fast                48 ns         48 ns   14725120
  BM_math_sincos                  43 ns         43 ns   16329843

Bug: N/A
Test: ran tests, benchmarks
Change-Id: I8693c64135233c0641af5302c38748f47ac76737
diff --git a/libm/Android.bp b/libm/Android.bp
index c3ed7ce..ec161fd 100644
--- a/libm/Android.bp
+++ b/libm/Android.bp
@@ -162,6 +162,8 @@
         "upstream-freebsd/lib/msun/src/s_significand.c",
         "upstream-freebsd/lib/msun/src/s_significandf.c",
         "upstream-freebsd/lib/msun/src/s_sin.c",
+        "upstream-freebsd/lib/msun/src/s_sincos.c",
+        "upstream-freebsd/lib/msun/src/s_sincosf.c",
         "upstream-freebsd/lib/msun/src/s_sinf.c",
         "upstream-freebsd/lib/msun/src/s_tan.c",
         "upstream-freebsd/lib/msun/src/s_tanf.c",
@@ -201,7 +203,6 @@
 
         // Functionality not in the BSDs.
         "significandl.c",
-        "sincos.c",
         "fake_long_double.c",
 
         // Home-grown stuff.
@@ -250,6 +251,7 @@
                 "upstream-freebsd/lib/msun/src/s_rintl.c",
                 "upstream-freebsd/lib/msun/src/s_roundl.c",
                 "upstream-freebsd/lib/msun/src/s_scalbnl.c",
+                "upstream-freebsd/lib/msun/src/s_sincosl.c",
                 "upstream-freebsd/lib/msun/src/e_sinhl.c",
                 "upstream-freebsd/lib/msun/src/s_sinl.c",
                 "upstream-freebsd/lib/msun/src/s_tanhl.c",