iwlwifi: correct debugfs data dumped from sram

the sram data dumped through the debugfs interface would only work properly
when dumping data on even u32 boundaries and swap bytes based on endianness
on that boundary making byte arrays impossible to read.

now addresses are displayed at the start of every line and the data is
displayed consistently if dumping 1 byte or 20 and regardless of what is the
starting address.

if no lenght given, address displayed is u32 in device format

Signed-off-by: Jay Sternberg <jay.e.sternberg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>