llvmPackages_18.lldb: fix build with gcc15

- add patch from upstream commit that was not backported to llvm_18:

https://github.com/llvm/llvm-project/commit/bb59f04e7e75dcbe39f1bf952304a157f0035314
Fixes build failure with gcc15:
```
In file included from /build/lldb-src-18.1.8/lldb/source/Utility/AddressableBits.cpp:9:
/build/lldb-src-18.1.8/lldb/include/lldb/Utility/AddressableBits.h:25:27:
error: 'uint32_t' has not been declared
   25 |   void SetAddressableBits(uint32_t addressing_bits);
      |                           ^~~~~~~~
/build/lldb-src-18.1.8/lldb/include/lldb/Utility/AddressableBits.h:13:1:
note: 'uint32_t' is defined in header '<cstdint>'; this is probably
fixable by adding '#include <cstdint>'
   12 | #include "lldb/lldb-forward.h"
  +++ |+#include <cstdint>
   13 |
```

Cannot use `fetchpatch` because patch does not apply on llvm_18
(no `#include "lldb/lldb-public.h"` line on llvm_18).

pkgs/development/compilers/llvm/common/lldb/default.nix

@@ -70,7 +70,14 @@ stdenv.mkDerivation (
 
     sourceRoot = "${finalAttrs.src.name}/lldb";
 
-    patches = [ ./gnu-install-dirs.patch ];
+    patches = [
+      ./gnu-install-dirs.patch
+    ]
+    ++ lib.optional (lib.versions.major release_version == "18") [
+      # Fix build with gcc15
+      # https://github.com/llvm/llvm-project/commit/bb59f04e7e75dcbe39f1bf952304a157f0035314
+      ./lldb-add-include-cstdint.patch
+    ];
 
     nativeBuildInputs = [
       cmake

pkgs/development/compilers/llvm/common/lldb/lldb-add-include-cstdint.patch

@@ -0,0 +1,16 @@
+Rebase of upstream commit:
+https://github.com/llvm/llvm-project/commit/bb59f04e7e75dcbe39f1bf952304a157f0035314
+
+diff --git a/include/lldb/Utility/AddressableBits.h b/include/lldb/Utility/AddressableBits.h
+index 0d27c3561ec27..8c7a1ec5f52c0 100644
+--- a/include/lldb/Utility/AddressableBits.h
++++ b/include/lldb/Utility/AddressableBits.h
+@@ -12,6 +12,8 @@
+ #include "lldb/lldb-forward.h"
+ 
++#include <cstdint>
++
+ namespace lldb_private {
+ 
+ /// \class AddressableBits AddressableBits.h "lldb/Core/AddressableBits.h"
+