Bump pack dev-drop version.
<url>http://www.keil.com/pack/</url>
<releases>
- <release version="5.7.0-dev0">
+ <release version="5.7.0-dev1">
Active development...
CMSIS-Core(M): 5.4.0 (see revision history for details)
- Enhanced MVE support for Armv8.1-MML
