[ELF] - Print options aliases in --help

This is PR30422,
previously LLD did not render all option aliases in --help.
With this patch it will.

Differential revision: https://reviews.llvm.org/D35477

llvm-svn: 309089
diff --git a/lld/test/ELF/help.s b/lld/test/ELF/help.s
new file mode 100644
index 0000000..25545315
--- /dev/null
+++ b/lld/test/ELF/help.s
@@ -0,0 +1,5 @@
+# RUN: ld.lld --help 2>&1 | FileCheck %s
+# CHECK:  OPTIONS:
+# CHECK:  --output=<value>        Path to file to write output
+# CHECK:  --output <value>        Path to file to write output
+# CHECK:  -o <path>               Path to file to write output