ci(workflows): update gcc version in build commands

Use consistent gcc-15.2.0 version for both CROSS_COMPILE and CC variables to avoid potential build issues

Author: TheWildJames

.github/workflows/sultan.yml

@@ -190,8 +190,8 @@ jobs:
           echo "Changing to configuration directory: $CONFIG..."
           cd "$CONFIG"
           
-          make CROSS_COMPILE=$GITHUB_WORKSPACE/gcc-15.2.0-nolibc/aarch64-linux/bin/aarch64-linux- CC=$GITHUB_WORKSPACE/gcc-14.2.0-nolibc/aarch64-linux/bin/aarch64-linux-gcc -j$(nproc --all) ${{ inputs.codename }}_defconfig
-          make CROSS_COMPILE=$GITHUB_WORKSPACE/gcc-15.2.0-nolibc/aarch64-linux/bin/aarch64-linux- CC=$GITHUB_WORKSPACE/gcc-14.2.0-nolibc/aarch64-linux/bin/aarch64-linux-gcc -j$(nproc --all)
+          make CROSS_COMPILE=$GITHUB_WORKSPACE/gcc-15.2.0-nolibc/aarch64-linux/bin/aarch64-linux- CC=$GITHUB_WORKSPACE/gcc-15.2.0-nolibc/aarch64-linux/bin/aarch64-linux-gcc -j$(nproc --all) ${{ inputs.codename }}_defconfig
+          make CROSS_COMPILE=$GITHUB_WORKSPACE/gcc-15.2.0-nolibc/aarch64-linux/bin/aarch64-linux- CC=$GITHUB_WORKSPACE/gcc-15.2.0-nolibc/aarch64-linux/bin/aarch64-linux-gcc -j$(nproc --all)
 
       - name: Copy Images
         run: |