MDEV-29222 - Fix mysqld_safe script

The mysqld_safe script was using bad grep options. The line that was fixed was likely meant to be 2 separate grep commands, piped into each other, with each one removing any lines that matched. The `-E` option was unneeded, as the command is not using regex.

Author: AddisonG

scripts/CMakeLists.txt

@@ -146,7 +146,7 @@ IF(UNIX)
  # 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")
+ "ps wwwp $PID | grep -v mariadbd-safe | grep -v mysqld_safe | grep -- $MYSQLD > /dev/null")
 ENDIF()
 IF(NOT FIND_PROC AND CMAKE_SYSTEM_NAME MATCHES "SunOS")
  SET (FIND_PROC