undefine macro before redefining
undefine macro before redefining

Fixes
src/main.c:89:9: error: 'printf' macro redefined [-Werror,-Wmacro-redefined]

Signed-off-by: Khem Raj <729d64b6f67515e258459a5f6d20ec88b2caf8df@gmail.com>

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