libc: hide __signalfd4 symbol

Bug: http://b/26274444
Change-Id: Iaa2df640cac07e2e407ca11b9701ee9e11729146
diff --git a/libc/libc.arm.brillo.map b/libc/libc.arm.brillo.map
index 9cef643..5d8f6ed 100644
--- a/libc/libc.arm.brillo.map
+++ b/libc/libc.arm.brillo.map
@@ -164,7 +164,6 @@
     __set_tls; # arm mips
     __sF;
     __sigaction; # arm x86 mips
-    __signalfd4; # arm x86 mips
     __snprintf_chk;
     __socket; # arm x86 mips
     __sprintf_chk;
diff --git a/libc/libc.arm.map b/libc/libc.arm.map
index c9f8708..8ab63a4 100644
--- a/libc/libc.arm.map
+++ b/libc/libc.arm.map
@@ -165,7 +165,6 @@
     __set_tls; # arm mips
     __sF;
     __sigaction; # arm x86 mips
-    __signalfd4; # arm x86 mips
     __snprintf_chk;
     __socket; # arm x86 mips
     __sprintf_chk;
diff --git a/libc/libc.map.txt b/libc/libc.map.txt
index b1322a2..dbce174 100644
--- a/libc/libc.map.txt
+++ b/libc/libc.map.txt
@@ -167,7 +167,6 @@
     __set_tls; # arm mips
     __sF;
     __sigaction; # arm x86 mips
-    __signalfd4; # arm x86 mips
     __snprintf_chk;
     __socket; # arm x86 mips
     __sprintf_chk;
diff --git a/libc/libc.mips.brillo.map b/libc/libc.mips.brillo.map
index 965927a..69f8f40 100644
--- a/libc/libc.mips.brillo.map
+++ b/libc/libc.mips.brillo.map
@@ -162,7 +162,6 @@
     __set_tls; # arm mips
     __sF;
     __sigaction; # arm x86 mips
-    __signalfd4; # arm x86 mips
     __snprintf_chk;
     __socket; # arm x86 mips
     __sprintf_chk;
diff --git a/libc/libc.mips.map b/libc/libc.mips.map
index 59ea26b..79ff4ee 100644
--- a/libc/libc.mips.map
+++ b/libc/libc.mips.map
@@ -163,7 +163,6 @@
     __set_tls; # arm mips
     __sF;
     __sigaction; # arm x86 mips
-    __signalfd4; # arm x86 mips
     __snprintf_chk;
     __socket; # arm x86 mips
     __sprintf_chk;
diff --git a/libc/libc.x86.brillo.map b/libc/libc.x86.brillo.map
index c19e797..743a485 100644
--- a/libc/libc.x86.brillo.map
+++ b/libc/libc.x86.brillo.map
@@ -162,7 +162,6 @@
     __set_tid_address; # arm x86 mips
     __sF;
     __sigaction; # arm x86 mips
-    __signalfd4; # arm x86 mips
     __snprintf_chk;
     __socket; # arm x86 mips
     __sprintf_chk;
diff --git a/libc/libc.x86.map b/libc/libc.x86.map
index 51f617e..f178cd3 100644
--- a/libc/libc.x86.map
+++ b/libc/libc.x86.map
@@ -163,7 +163,6 @@
     __set_tid_address; # arm x86 mips
     __sF;
     __sigaction; # arm x86 mips
-    __signalfd4; # arm x86 mips
     __snprintf_chk;
     __socket; # arm x86 mips
     __sprintf_chk;