scull: Makefile: Declare LDDINC variable earlier

Move the definition of LDDINC earlier into the file. This prevents the
following compile time error: implicit declaration of function ‘KBUILD_STR’.
Don't use create_proc_entry() and create_proc_read_entry()

Don't use create_proc_entry() and create_proc_read_entry() as they
are deprecated, but rather use proc_create() and proc_create_data()
respectively and seq_file instead.
scull: pipe: Remove unused commented line

Remove commented line with deprecated create_proc_read_entry call
that was forgotten to remove.
scull: main | pipe : Fix coding style

Replace white space indentation introduced with the previous patch
with 8 characters width TABs to comply with the kernel coding style.
Merge pull request #3 from luiorpe1/scull-3.10

Scull updated for 3.10