Always print the initial bugreport progress message.

Otherwise, it might take seconds to display the initial percentage,
and the user might thing something is wrong and CTRL-C the process.

Fixes: 62003852
Test: added BugreportTest.OkProgressZeroPercentIsNotIgnored
Test: m -j32 adb_test && ./out/host/linux-x86/nativetest64/adb_test/adb_test --gtest_filter=BugreportTest.*

Change-Id: I8e7dbb28666c825c1408d5d204f813064fc3048f