Update README.md

BOLT supports DWARF5.

bolt/README.md

@@ -30,14 +30,6 @@ compiler option. Since GCC8 enables this option by default, you have to
 explicitly disable it by adding `-fno-reorder-blocks-and-partition` flag if
 you are compiling with GCC8 or above.
 
-NOTE2: DWARF v5 is the new debugging format generated by the latest LLVM and GCC
-compilers. It offers several benefits over the previous DWARF v4. Currently, the
-support for v5 is a work in progress for BOLT. While you will be able to
-optimize binaries produced by the latest compilers, until the support is
-complete, you will not be able to update the debug info with
-`-update-debug-sections`. To temporarily work around the issue, we recommend
-compiling binaries with `-gdwarf-4` option that forces DWARF v4 output.
-
 PIE and .so support has been added recently. Please report bugs if you
 encounter any issues.