doc(README): add lfortran version & fpm command

Author: rouson

README.md

@@ -195,6 +195,7 @@ Compiler/Runtime  |Tested Versions|Run Type|Example build/test commands (paralle
 LLVM/[Caffeine]   |22.0.0git      |parallel|`fpm test --compiler flang-new --flag "-O3 -DHAVE_MULTI_IMAGE_SUPPORT -fcoarray" --link-flag "-lcaffeine -lgasnet-smp-seq -L<caffeine-path> -L<gasnet-path>"`
 LLVM              |20-22          |serial  |`fpm test --compiler flang-new --flag -O3`
 LLVM              |19             |serial  |`fpm test --compiler flang-new --flag "-O3 -mmlir -allow-assumed-rank"`
+LFortran          |0.60.0-421-ge2c448c79 |serial  |`fpm test --compiler lfortran --flag "--cpp --realloc-lhs-arrays --separate-compilation"`
 NAG               |7.2, Build 7235|parallel|`NAGFORTRAN_NUM_IMAGES=2 fpm test --compiler nagfor --flag "-fpp -O3 -coarray"`
 Intel             |2025.2.{0-1}   |parallel|`FOR_COARRAY_NUM_IMAGES=2 fpm test --compiler ifx --flag "-fpp -O3 -coarray" --profile release`
 GCC/[OpenCoarrays]|14-15          |serial  |`fpm test --compiler gfortran --profile release`