Here is a non-cursor version of your sript:

Declare @Prefix varchar(255)

Declare @tmpstr varchar(MAX)

Set @Prefix = '

exec master.dbo.sp_addsrvrolemember @loginame='''

Set @tmpstr=''

Select @tmpstr = @tmpstr

+ Case When sysadmin = 1 Then @Prefix + [LoginName] + ''', @rolename=''sysadmin''' Else '' End

+ Case When securityadmin = 1 Then @Prefix + [LoginName] + ''', @rolename=''securityadmin''' Else '' End

+ Case When serveradmin = 1 Then @Prefix + [LoginName] + ''', @rolename=''serveradmin''' Else '' End

+ Case When setupadmin = 1 Then @Prefix + [LoginName] + ''', @rolename=''setupadmin''' Else '' End

+ Case When processadmin = 1 Then @Prefix + [LoginName] + ''', @rolename=''processadmin''' Else '' End

+ Case When diskadmin = 1 Then @Prefix + [LoginName] + ''', @rolename=''diskadmin''' Else '' End

+ Case When dbcreator = 1 Then @Prefix + [LoginName] + ''', @rolename=''dbcreator''' Else '' End

+ Case When bulkadmin = 1 Then @Prefix + [LoginName] + ''', @rolename=''bulkadmin''' Else '' End

From (select convert(varchar(100),suser_sname(sid)) as [LoginName],

sysadmin,

securityadmin,

serveradmin,

setupadmin,

processadmin,

diskadmin,

dbcreator,

bulkadmin

from sys.syslogins

where sysadmin<>0

or securityadmin<>0

or serveradmin<>0

or setupadmin <>0

or processadmin <>0

or diskadmin<>0

or dbcreator<>0

or bulkadmin<>0) L

Print @tmpstr