NVIDIA: SAUCE: GitHub Actions: Add libdw-dev

Fix building error on new kernel versions:
scripts/gendwarfksyms/gendwarfksyms.h:6:10: fatal error: dwarf.h: No such file or directory
    6 | #include <dwarf.h>
      |          ^~~~~~~~~

Signed-off-by: Nirmoy Das <nirmoyd@nvidia.com>

Author: nirmoy

.github/workflows/pr-build.yml

@@ -54,7 +54,7 @@ jobs:
       - name: Install Dependencies
         run: |
           sudo apt-get update
-          sudo apt-get install -y build-essential libncurses-dev bison flex libssl-dev libelf-dev python3
+          sudo apt-get install -y build-essential libncurses-dev bison flex libssl-dev libelf-dev python3 libdw-dev
 
       - name: Configure Kernel
         run: |