Switch last few benchmarks over to using SCALE_FACTOR.

Most of the benchmarks define a constant SCALE_FACTOR that controls
how many times we should repeat the benchmark.  This patch brings the
last few benchmarks into line.

ChangeLog:

	* 2dfir/fir2dim.c (SCALE_FACTOR): Added.
	(main) Switch to use SCALE_FACTOR.
	* blowfish/bf.c: Likewise.
	* crc32/crc_32.c: Likewise.
	* cubic/basicmath_small.c: Likewise.
	* dijkstra/dijkstra_small.c: Likewise.
	* fdct/fdct.c: Likewise.
	* float_matmult/matmult.c: Likewise.
	* int_matmult/matmult.c: Likewise.
	* rijndael/aesxam.c: Likewise.
	* sha/sha_driver.c: Likewise.