Add QNX fixes from Kardos, Dr. Andreas

doc/FAQ_QNX4

src/test/regress/expected/float4-exp-three-digits.out

src/test/regress/expected/float8-exp-three-digits.out

src/test/regress/expected/int8-exp-three-digits.out

src/test/regress/regress.sh

src/test/regress/resultmap