NEWS: add various core changes and arm64 additions

Add demangler update, __libc_freeres not being called on fatal signal,
DWARF reader improvements, glibc 2.34 support and various new arm64
v8.2 updates.

Remove Tool Changes section, since there were no user visible
changes to the tools in 3.18.0.

NEWS

@@ -10,10 +10,27 @@ AMD64/macOS 10.13 and nanoMIPS/Linux.
 
 * ==================== CORE CHANGES ===================
 
+  - The libiberty demangler has been updated, which brings support
+    for Rust v0 name demangling
+
+  - __libc_freeres isn't called anymore after the program recieves
+    a fatal signal. Causing some internal glibc resources to hang
+    around, but preventing any crashes after the program has ended.
+
+  - The DWARF reader is now much faster at startup when just
+    --read-inline-info=yes (the default in most cases) is given.
+
+  - glibc 2.34, which moved various functions from libpthread.so
+    into libc.so, is now supported.
+
 * ================== PLATFORM CHANGES =================
 
 * arm64:
 
+  - v8.2 scalar and vector FABD, FACGE, FACGT and FADD.
+  - v8.2 FP compare & conditional compare instructions.
+  - Zero variants of v8.2 FP compare instructions.
+
 * s390:
 
   - Support the miscellaneous-instruction-extensions facility 3 and the
@@ -29,8 +46,6 @@ AMD64/macOS 10.13 and nanoMIPS/Linux.
  
 * Support for X86/FreeBSD and AMD64/FreeBSD has been added.
 
-* ==================== TOOL CHANGES ====================
-
 * ==================== FIXED BUGS ====================
 
 The following bugs have been fixed or resolved.  Note that "n-i-bz"