[202205] Update Broadcom DNX SAI version to 7.1.50.4 (#15561)

DNX fixes:

CS00012287482 - support for 1024 LAGs on DNX

Other changes (XGS fixes)

SID - L3 multicast packet drop due to wrong VFI derivation - SDK-350470
SID - SIGSEGV in linkscan callback delivery - SDK-287578
SID - Repeated VXLAN calls deletes vlan translation action profile SDK-313980
SER - error in IS_TDM_CALENDAR0/1 can cause traffic hit in TH
SID - L2_ENTRY Table Lookups May Miss
[CSP CS00012275452] sai_object_type_get_availability failed with SAI_STATUS_INVALID_PARAMETER

platform/broadcom/sai.mk

@@ -1,5 +1,5 @@
 LIBSAIBCM_XGS_VERSION = 7.1.36.4
-LIBSAIBCM_DNX_VERSION = 7.1.42.4
+LIBSAIBCM_DNX_VERSION = 7.1.50.4
 LIBSAIBCM_BRANCH_NAME = REL_7.0_202205
 LIBSAIBCM_XGS_URL_PREFIX = "https://sonicstorage.blob.core.windows.net/public/sai/bcmsai/$(LIBSAIBCM_BRANCH_NAME)/$(LIBSAIBCM_XGS_VERSION)"
 LIBSAIBCM_DNX_URL_PREFIX = "https://sonicstorage.blob.core.windows.net/public/sai/bcmsai/$(LIBSAIBCM_BRANCH_NAME)/$(LIBSAIBCM_DNX_VERSION)"