Summarize build options in configure script
Summary: This is a backport of secp256k1's PR518
Test Plan:
Verify output of configure during the make build:
Build Options: with endomorphism = no with ecmult precomp = yes with jni = no with benchmarks = yes with coverage = no module ecdh = no module recovery = yes module multiset = yes module schnorr = yes asm = x86_64 bignum = no field = 64bit scalar = 64bit CC = gcc CFLAGS = -g -O2 -W -std=c89 -pedantic -Wall -Wextra -Wcast-align -Wnested-externs -Wshadow -Wstrict-prototypes -Wno-unused-function -Wno-long-long -Wno-overlength-strings -fvisibility=hidden -O3 CPPFLAGS = LDFLAGS =
Reviewers: #bitcoin_abc, Fabien
Reviewed By: #bitcoin_abc, Fabien
Differential Revision: https://reviews.bitcoinabc.org/D4981