This fixes the following compilation warnings:
mraa/src/src/mock/mock_board.c: In function ‘mraa_mock_board’:
mraa/src/src/mock/mock_board.c:156:5: warning: ‘strncpy’ output truncated before terminating nul copying 8 bytes from a string of the same length [-Wstringop-truncation]
156 | strncpy(b->pins[pos].name, "SPI0MOSI", 8);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mraa/src/src/mock/mock_board.c:162:5: warning: ‘strncpy’ output truncated before terminating nul copying 8 bytes from a string of the same length [-Wstringop-truncation]
162 | strncpy(b->pins[pos].name, "SPI0MISO", 8);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mraa/src/src/mock/mock_board.c:168:5: warning: ‘strncpy’ output truncated before terminating nul copying 8 bytes from a string of the same length [-Wstringop-truncation]
168 | strncpy(b->pins[pos].name, "SPI0SCLK", 8);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Alex T <alext.mkrs@gmail.com>