I have no experience with these things, so someone please correct me if I am wrong:
The title of the thread indicates that it is an ARMIPS module. It appears that the "ArmIPS Pack" downloads are assembly code intended for use with the ARMIPS Assembler.https://github.com/Kingcom/armips
The ARMIPS assembler is "for various ARM and MIPS platforms". ARM and MIPS are two different CPU architectures (like PowerPC or x86) and are not particularly related to "IPS patches". (I don't know why they decided to write it as "ArmIPS" in that thread. That just seems to be confusing.)
Opening up "InfiniteCOs11.zip", I find main.asm, which contains the line
.open aw2-original.gba, aw2-infinite.gba, 0x08000000
So, I'm guessing you need to download the Win32 version of ARMIPS, rename your Advance Wars 2 ROM to aw2-original.gba, put it in the same folder as main.asm, and then run "armips main.asm" from the command line. Make sense?
That will produce aw2-infinite.gba, and you can then use Lunar IPS to make an IPS patch by comparing aw2-infinite.gba to aw2-original.gba.