Update README.md

Author: tpadioleau

README.md

@@ -57,10 +57,10 @@ To use DDC components, one needs the following dependencies:
 ## Getting the code and basic configuration
 
 ```bash
-git clone --recurse-submodules -j4 https://github.com/CExA-project/ddc.git
+git clone --recurse-submodules --jobs 4 https://github.com/CExA-project/ddc.git
 cd ddc
-cmake -B build -D DDC_BUILD_KERNELS_FFT=OFF -D DDC_BUILD_KERNELS_SPLINES=OFF -D DDC_BUILD_PDI_WRAPPER=OFF
-cmake --build build
+cmake -D DDC_BUILD_KERNELS_FFT=OFF -D DDC_BUILD_KERNELS_SPLINES=OFF -D DDC_BUILD_PDI_WRAPPER=OFF -B build
+cmake --build build --parallel 4
 ```
 
 ## Contributing