drivers/: Make 'internal_delay' the default unless defined

Drop the explicit need to specify the default 'internal_delay'
callback function pointer in the programmer_entry struct.
This is a reasonable default for every other driver in the
tree with only the two exceptions of ch341a_spi.c and serprog.c.

Thus this simplifies driver development.

Change-Id: I17460bc2c0aebcbb48c8dfa052b260991525cc49
Signed-off-by: Edward O'Callaghan <quasisec@google.com>
---
M atahpt.c
M atapromise.c
M atavia.c
M buspirate_spi.c
M dediprog.c
M developerbox_spi.c
M digilent_spi.c
M drkaiser.c
M dummyflasher.c
M flashrom.c
M ft2232_spi.c
M gfxnvidia.c
M internal.c
M it8212.c
M jlink_spi.c
M linux_mtd.c
M linux_spi.c
M mediatek_i2c_spi.c
M mstarddc_spi.c
M ni845x_spi.c
M nic3com.c
M nicintel.c
M nicintel_eeprom.c
M nicintel_spi.c
M nicnatsemi.c
M nicrealtek.c
M ogp_spi.c
M parade_lspcon.c
M pickit2_spi.c
M pony_spi.c
M raiden_debug_spi.c
M rayer_spi.c
M realtek_mst_i2c_spi.c
M satamv.c
M satasii.c
M stlinkv3_spi.c
M usbblaster_spi.c
37 files changed, 23 insertions(+), 42 deletions(-)