Fix build dependencies.

Author: davidgiven

.github/workflows/ccpp.yml

@@ -11,7 +11,7 @@ jobs:
         repository: 'davidgiven/cpm65'
 
     - name: apt
-      run: sudo apt update && sudo apt install cc1541 cpmtools libfmt-dev fp-compiler moreutils mame srecord 64tass libreadline-dev
+      run: sudo apt update && sudo apt install cc1541 cpmtools libfmt-dev fp-compiler moreutils mame srecord 64tass libreadline-dev libelf-dev
 
     - name: install llvm-mos
       run: |

.github/workflows/release.yml

@@ -15,7 +15,7 @@ jobs:
         path: 'cpm65'
 
     - name: apt
-      run: sudo apt update && sudo apt install cc1541 cpmtools libfmt-dev fp-compiler moreutils srecord 64tass libreadline-dev
+      run: sudo apt update && sudo apt install cc1541 cpmtools libfmt-dev fp-compiler moreutils srecord 64tass libreadline-dev libelf-dev
 
     - name: install llvm-mos
       run: |