Revert "Set SA_RESTORER in sigaction()"

This reverts commit e4fa46e75cd0d433b5c6c064720ed7e195cba7c8.
diff --git a/libc/arch-arm/syscalls/__sigaction.S b/libc/arch-arm/syscalls/sigaction.S
similarity index 81%
rename from libc/arch-arm/syscalls/__sigaction.S
rename to libc/arch-arm/syscalls/sigaction.S
index aba44b8..2696f1e 100644
--- a/libc/arch-arm/syscalls/__sigaction.S
+++ b/libc/arch-arm/syscalls/sigaction.S
@@ -2,12 +2,12 @@
 #include <sys/linux-syscalls.h>
 
     .text
-    .type __sigaction, #function
-    .globl __sigaction
+    .type sigaction, #function
+    .globl sigaction
     .align 4
     .fnstart
 
-__sigaction:
+sigaction:
     .save   {r4, r7}
     stmfd   sp!, {r4, r7}
     ldr     r7, =__NR_sigaction