Unix/Signals.inc: Fix a typo. Thanks to Dani Berg!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163288 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Unix/Signals.inc b/lib/Support/Unix/Signals.inc
index 5195116..aac0408 100644
--- a/lib/Support/Unix/Signals.inc
+++ b/lib/Support/Unix/Signals.inc
@@ -293,7 +293,7 @@
 #endif
 }
 
-/// PrintStackTraceOnErrorSignal - When an error signal (such as SIBABRT or
+/// PrintStackTraceOnErrorSignal - When an error signal (such as SIGABRT or
 /// SIGSEGV) is delivered to the process, print a stack trace and then exit.
 void llvm::sys::PrintStackTraceOnErrorSignal() {
   AddSignalHandler(PrintStackTrace, 0);