[bazel][libc] Update Bazel rules for fmodbf16 math function that was added in 96b1dfb (#157143)

Author: lexi-nadia

utils/bazel/llvm-project-overlay/libc/BUILD.bazel

@@ -3748,6 +3748,13 @@ libc_math_function(
     ],
 )
 
+libc_math_function(
+    name = "fmodbf16",
+    additional_deps = [
+        ":__support_fputil_generic_fmod",
+    ],
+)
+
 libc_math_function(
     name = "fmodf",
     additional_deps = [

utils/bazel/llvm-project-overlay/libc/test/src/math/smoke/BUILD.bazel

@@ -738,6 +738,11 @@ math_test(
     hdrs = ["FModTest.h"],
 )
 
+math_test(
+    name = "fmodbf16",
+    hdrs = ["FModTest.h"],
+)
+
 math_test(
     name = "fmodf",
     hdrs = ["FModTest.h"],