Remove useless _C_LABEL from our assembler source.

Change-Id: I41a9181537c70ecc69ef8035132c9a83811a40d0
diff --git a/libc/arch-x86/bionic/sigsetjmp.S b/libc/arch-x86/bionic/sigsetjmp.S
index 70cc6db..69494b4 100644
--- a/libc/arch-x86/bionic/sigsetjmp.S
+++ b/libc/arch-x86/bionic/sigsetjmp.S
@@ -43,9 +43,9 @@
 	PIC_PROLOGUE
 	pushl	$0
 #ifdef PIC
-	call	PIC_PLT(_C_LABEL(sigblock))
+	call	PIC_PLT(sigblock)
 #else
-	call	_C_LABEL(sigblock)
+	call	sigblock
 #endif
 	addl	$4,%esp
 	PIC_EPILOGUE
@@ -71,9 +71,9 @@
 	PIC_PROLOGUE
 	pushl	24(%edx)
 #ifdef PIC
-	call	PIC_PLT(_C_LABEL(sigsetmask))
+	call	PIC_PLT(sigsetmask)
 #else
-	call	_C_LABEL(sigsetmask)
+	call	sigsetmask
 #endif
 	addl	$4,%esp
 	PIC_EPILOGUE