Try removing some bandaid -Wno

We've collected multiple -Wno-xxx settings while working around small
issues with the SDK.  Remove them and see where we stand

Author: earlephilhower

platform.txt

@@ -47,7 +47,7 @@ compiler.warning_flags=-Werror=return-type -Wno-psabi
 compiler.warning_flags.none=-Werror=return-type -Wno-psabi
 compiler.warning_flags.default=-Werror=return-type -Wno-psabi
 compiler.warning_flags.more=-Wall -Werror=return-type -Wno-ignored-qualifiers -Wno-psabi
-compiler.warning_flags.all=-Wall -Wextra -Werror=return-type -Wno-ignored-qualifiers -Wno-psabi -Wno-unused-parameter -Wno-missing-field-initializers
+compiler.warning_flags.all=-Wall -Wextra -Werror=return-type -Wno-psabi
 
 compiler.netdefines={build.libpicowdefs} -DLWIP_IGMP=1 -DLWIP_CHECKSUM_CTRL_PER_NETIF=1
 compiler.psramdefines={build.psram_cs} {build.psram_freq}