Fix unmatched file identifications

Hi,

I found that there are two .c and .h files whose identification in the
header comment doesn't match its actual path.

src/include/common/compression.h has:

  * IDENTIFICATION
  *        src/common/compression.h
  *-------------------------------------------------------------------------

src/fe_utils/cancel.c has:

  * src/fe-utils/cancel.c
  *
  *------------------------------------------------------------------------

The attached small patch fixes them.

Regards,

-- 
Masahiko Sawada
EDB:  https://www.enterprisedb.com/