lib/atoi/a2i/: Simplify these macros by calling a2i()

[alejandro-colomar]

I applied a similar patch in liba2i, where I've tested it.

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Revisions:

v1b

• Rebase

$ git range-diff master..gh/a2i shadow/master..a2i 
1:  c2c3495c = 1:  dc458930 lib/atoi/a2i/: Simplify these macros by calling a2i()

v1c

• Rebase

$ git range-diff master..gh/a2i shadow/master..a2i 
1:  dc458930 = 1:  b07b5b62 lib/atoi/a2i/: Simplify these macros by calling a2i()

v1d

• Rebase

$ git range-diff master..gh/a2i shadow/master..a2i 
1:  b07b5b62 = 1:  3f55095a lib/atoi/a2i/: Simplify these macros by calling a2i()

v1e

• Rebase

$ git range-diff master..gh/a2i shadow/master..a2i 
1:  3f55095a = 1:  4048fbc4 lib/atoi/a2i/: Simplify these macros by calling a2i()

v1f

• Rebase

$ git range-diff alx/master..gh/a2i master..a2i 
1:  4048fbc4 = 1:  5b614be3 lib/atoi/a2i/: Simplify these macros by calling a2i()

[alejandro-colomar]

Queued after the release of 4.17.0.