mysqld_safe script breaks with many versions of grep

When running the mysqld_safe start command, if the grep command isn't the exact correct version, it will fail with the following error:

grep: mysqld_safe: No such file or directory

This is a problem, as the script should not assume that the grep command that is installed should have all the features.
It is failing with very common versions of grep, like GNU grep v3.7

This was broken in commit 193bfdd831bbbf65e74acd12baf691d4305e3c11.

The offending line of code is in server/scripts/CMakeLists.txt:

  # FIND_PROC and CHECK_PID are used by mysqld_safe

IF(CMAKE_SYSTEM_NAME MATCHES "Linux")

  SET (FIND_PROC

    "ps wwwp $PID | grep -vE mariadbd-safe -vE mysqld_safe | grep -- $MYSQLD > /dev/null")

This could be fixed by changing the middle grep command from

grep -vE mariadbd-safe -vE mysqld_safe

To the new command:

grep -vE "mariadbd-safe|mysqld_safe"