add branches to git modules

.gitmodules

 [submodule "accelerator_wrapper_tech"]
 	path = accelerator_wrapper_tech
-url = https://git.soton.ac.uk/soclabs/accelerator_wrapper_tech.git
+	url = https://git.soton.ac.uk/soclabs/accelerator_wrapper_tech.git
+	branch = main
 [submodule "nanosoc_tech"]
 	path = nanosoc_tech
-url = https://git.soton.ac.uk/soclabs/nanosoc_tech.git
+	url = https://git.soton.ac.uk/soclabs/nanosoc_tech.git
+	branch = feat_nanosoc_regions
 [submodule "soctools_flow"]
 	path = soctools_flow
 	url = https://git.soton.ac.uk/soclabs/soctools_flow.git
+	branch = main
 [submodule "generic_lib_tech"]
 	path = generic_lib_tech
 	url = https://git.soton.ac.uk/soclabs/generic_lib_tech.git
+	branch = main
 [submodule "fpga_lib_tech"]
 	path = fpga_lib_tech
 	url = https://git.soton.ac.uk/soclabs/fpga_lib_tech.git
+	branch = main
 [submodule "rtl_primitives_tech"]
 	path = rtl_primitives_tech
 	url = https://git.soton.ac.uk/soclabs/rtl_primitives_tech.git
+	branch = main
 [submodule "secworks-aes"]
 	path = secworks-aes
 	url = https://github.com/secworks/aes.git
+	branch = master