add very small dff sram variant (no 4k SRAMs)

diff --git a/libreriscv b/libreriscv
index 1f6cef361a43cbc95c49fa104e0d0f9ccf26fa92..84cababea353b8c1882eb3b1512438579c31d37c 160000 (submodule)
--- a/libreriscv
+++ b/libreriscv
@@ -1 +1 @@
-Subproject commit 1f6cef361a43cbc95c49fa104e0d0f9ccf26fa92
+Subproject commit 84cababea353b8c1882eb3b1512438579c31d37c

diff --git a/src/soc/litex/florent b/src/soc/litex/florent
index 9485f4c64e46754082d921f2c8b251f1dab20338..cba78e3d60e6f67ce99adbdcbf6a09f9728dc849 160000 (submodule)
--- a/src/soc/litex/florent
+++ b/src/soc/litex/florent
@@ -1 +1 @@
-Subproject commit 9485f4c64e46754082d921f2c8b251f1dab20338
+Subproject commit cba78e3d60e6f67ce99adbdcbf6a09f9728dc849