Rename dprintf() debugging macro do debugprintf()

[tbaederr]

dprintf() is a function in libc and might be included when including
stdio.h:

./sysfs.h:59:9: warning: 'dprintf' macro redefined [-Wmacro-redefined]
^
/usr/include/bits/stdio2.h:148:12: note: previous definition is here
^
1 warning generated.

This can be reproduced by compiling with clang while specifying -Wp,-D_FORTIFY_SOURCE=2 -O2 as $CFLAGS.

[kamalesh-babulal]

Thanks for compiling it over clang. It's a matter of choice, but I am biased towards using the compact version for debugprintf() like dbg_printf().

[tbaederr]

Sure, updated the commit.