-- MAKE libxc WITH SRP FUNCTIONAL --

Just place gga_x_pbe_srp.c and make-libxc-erc2.bsh in the 
directory where src is and run the script. 

Modify xcoeff in gga_x_pbe_srp.c in order to change the 
mixing coefficient in the SRP functional.

The SRP functional will be implemented in place of the 
revPBE functional.