Update the llvm-objcopy documentation

Author: kuilpd

llvm/docs/CommandGuide/llvm-objcopy.rst

@@ -346,6 +346,18 @@ them.
  symbol, with leading and trailing whitespace ignored, as is anything following
  a '#'. Can be specified multiple times to read names from multiple files.
 
+.. option:: --ignore-symbol <symbol>
+
+ Do not change parameters of symbol <symbol> when executing other options that
+ can change the symbol's name, binding or visibility
+
+.. option:: --ignore-symbols <filename>
+
+ Reads a list of symbols from <filename> and runs as if --ignore-symbol=<symbol>
+ is set for each one. <filename> contains one symbol per line and may contain
+ comments beginning with '#'. Leading and trailing whitespace is stripped from
+ each line. May be repeated to read symbols from many files.
+
 .. option:: --input-target <format>, -I
 
  Read the input as the specified format. See `SUPPORTED FORMATS`_ for a list of