ext4: add missing KERN_CONT to a few more debugging uses

Recent commits require line continuing printks to always use
pr_cont or KERN_CONT.  Add these markings to a few more printks.

Miscellaneaous:

o Integrate the ea_idebug and ea_bdebug macros to use a single
  call to printk(KERN_DEBUG instead of 3 separate printks
o Use the more common varargs macro style

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>