stm8-binutils-gdb-20200322 release

The new stm8-binutils-gdb-20200322 release is available for download.

Changes:

• Small bug fixes in gas
• Fixed bit operand relocation
• Implemented .s short addressing mode modifer to index and ptr operands
• Include stm8 while building multi architecture gdb
• Fixed bccm instruction
• Added gas --gc-sections and hi8/lo8/hh8