Add u-boot binary and include core option in compile-kernel

.gitignore

 custom-kernels
 
 boot-ressources/rootfs.tar.bz2
-boot-ressources/u-boot-sunxi-with-spl.bin

scripts/compile-kernel

 #!/bin/bash
 
 usage() {
-  echo "Usage: $0 [-hgdkm] [-l LINUX_PATH] [-o OUTPUT_STR | -O OUTPUT_NAME] (-p | -u CONFIG_PATH | -c CONFIG_PATH | -n OLD_CONFIG_PATH NEW_CONFIG_PATH)"
+  echo "Usage: $0 [-hgdkm] [-j N_CORES] [-l LINUX_PATH] [-o OUTPUT_STR | -O OUTPUT_NAME] (-p | -u CONFIG_PATH | -c CONFIG_PATH | -n OLD_CONFIG_PATH NEW_CONFIG_PATH)"
   exit 1;
 }
 
 linux_path=$HOME/linux
 output_str=""
+nb_cores=4
 
-while getopts "hgdkmpsu:c:nl:o:O:" opt; do
+while getopts "hgdkmpsu:c:nl:o:O:j:" opt; do
   case "${opt}" in
     h )
         usage
@@ -55,6 +56,9 @@ while getopts "hgdkmpsu:c:nl:o:O:" opt; do
     O )
         output_name="${OPTARG}"
         ;;
+    j )
+        nb_cores="${OPTARG}"
+        ;;
     * )
         usage
       ;;
@@ -120,15 +124,15 @@ fi
 
 if [ -n "${compile_kernel}" ]; then
   echo "Compiling kernel...";
-  make -j20 LOADADDR=0x48000000 uImage;
+  make -j$nb_cores LOADADDR=0x48000000 uImage;
   echo "Kernel compilation done";
 fi
 
 if [ -n "${compile_modules}" ]; then
   echo "Compiling modules...";
-  make -j20 modules;
+  make -j$nb_cores modules;
   rm -rf output
-  make -j20 INSTALL_MOD_PATH=output modules modules_install;
+  make -j$nb_cores INSTALL_MOD_PATH=output modules modules_install;
   echo "Modules compilation done";
 fi
 
@@ -169,7 +173,7 @@ fi
 
 echo "Compressing archive...";
 cd ../$output_name;
-tar cf - * | pigz -9 -p 20 > ../$output_name.tar.gz;
+tar cf - * | pigz -9 -p $nb_cores > ../$output_name.tar.gz;
 cd ..;
 
 echo "Removing output folder...";