Add dependency on libm as required by #93

Jan Breuer

2017-08-16 4f960d20c76cb67e206a62f0e6c7608d75693ddc

 libscpi/src/lexer_private.h

@@ -58,6 +58,7 @@
    int scpiLex_Semicolon(lex_state_t * state, scpi_token_t * token) LOCAL;
    int scpiLex_Colon(lex_state_t * state, scpi_token_t * token) LOCAL;
    int scpiLex_NewLine(lex_state_t * state, scpi_token_t * token) LOCAL;
    int scpiLex_SpecificCharacter(lex_state_t * state, scpi_token_t * token, char chr) LOCAL;

#ifdef   __cplusplus
}