Revert "tty/serial: 8250: Sort drivers in Makefile"

JIRA: https://issues.redhat.com/browse/RHEL-69911

Upstream Status: RHEL9 only

This reverts cs9 commit 9291d262.

cs9 commit 9291d2620e37 is a backport of upstream commit  
66ebe67d1b68 ("tty/serial: 8250: Sort drivers in Makefile")  
  
Changing the order that source files are compiled and linked into  
the 8250 serial line driver also changes the order that the init  
routines in that driver are invoked. This can result in ttySn  
devices being enumerated differently, depending on configuration  
details.  
  
In the specific case of this JIRA, in RHEL 9.4:  
  
 1.1 Routine pciserial_init_one in drivers/tty/serial/8250/8250_pci.c  
     configures a PCI serial port as ttyS0.  
 1.2 Routine dw8250_probe in drivers/tty/serial/8250/8250_dw.c  
     configures two serial ports enumerated by ACPI as ttyS1, ttyS2.  
  
But in RHEL 9.5 where 8250_dw.c is moved ahead of 8250_pci.c:  
  
 2.1 Routine dw8250_probe in drivers/tty/serial/8250/8250_dw.c  
     configures two serial ports enumerated by ACPI as ttyS0, ttyS1.  
 2.2 Routine pciserial_init_one in drivers/tty/serial/8250/8250_pci.c  
     configures a PCI serial port as ttyS2.  
  
If at all possible, RHEL should avoid such user visible changes  
in a minor release. Therefore, for the duration of RHEL 9.x only,  
revert this change. But for RHEL 10, stay with the upstream change.  
  
Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>