Change in flashrom[master]: Makefile: Rework NI-845x detection

[Thomas Heijligen (Code Review)]

Attention is currently required from: Nico Huber, Miklós Márton, Angel Pons.
Thomas Heijligen has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/59047 )

Change subject: Makefile: Rework NI-845x detection
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Patch Set 12:

(1 comment)

File Makefile:

https://review.coreboot.org/c/flashrom/+/59047/comment/29c7dfd2_2381c03d 
PS11, Line 740: # hack to access env variable containing brackets...
              : PROGRAMFILES_X86DIR = $(shell env | sed -n "s/^PROGRAMFILES(X86)=//p")
              : 
              : ifneq ($(PROGRAMFILES_X86DIR),)
              : ifneq ($(PROGRAMFILES_X86DIR), ${PROGRAMFILES})
              : NI845X_LIBS += -L'$(PROGRAMFILES_X86DIR)\National Instruments\NI-845x\MS Visual C'
              : NI845X_INCLUDES += -I'$(PROGRAMFILES_X86DIR)\National Instruments\NI-845x\MS Visual C'
              : endif
              : endif
> I would like to maintain this unless Miklós agrees that it's not really needed […]

I've added this. I hope this is a acceptable compromise between newer readable code and the old behavior.