[nrf fromtree] samples: wifi: Add overlays for Enterprise mode

This overlay has all necessary configuration needed for Enterprise mode.
Two variants are given, once with fixed size network buffers and other
with variable size network buffers (still experimental).

Signed-off-by: Chaitanya Tata <[email protected]>
(cherry picked from commit d107b04)

Author: krish2718

samples/net/wifi/overlay-enterprise-variable-bufs.conf

@@ -0,0 +1,9 @@
+CONFIG_WIFI_NM_WPA_SUPPLICANT_CRYPTO_ENTERPRISE=y
+# EAP frames are ~1100 bytes, so, for efficiency, we set the data size to 1100
+CONFIG_NET_BUF_DATA_SIZE=1100
+# Use variable data size to reduce memory usage for small data packets
+CONFIG_NET_BUF_VARIABLE_DATA_SIZE=y
+# For TLS and X.509 processing MbedTLS needs large heap size and using separate heap
+# for MbedTLS gives us more control over the heap size.
+CONFIG_MBEDTLS_ENABLE_HEAP=y
+CONFIG_MBEDTLS_HEAP_SIZE=55000

samples/net/wifi/overlay-enterprise.conf

@@ -0,0 +1,10 @@
+CONFIG_WIFI_NM_WPA_SUPPLICANT_CRYPTO_ENTERPRISE=y
+# EAP frames are ~1100 bytes, so, need higher packet counts as default packet size is 128
+CONFIG_NET_PKT_TX_COUNT=36
+CONFIG_NET_PKT_RX_COUNT=36
+CONFIG_NET_BUF_TX_COUNT=72
+CONFIG_NET_BUF_RX_COUNT=36
+# For TLS and X.509 processing MbedTLS needs large heap size and using separate heap
+# for MbedTLS gives us more control over the heap size.
+CONFIG_MBEDTLS_ENABLE_HEAP=y
+CONFIG_MBEDTLS_HEAP_SIZE=55000