Impossible to tell for sure from the photos, but this looks like pretty typical winter burn - damaged leaves from winter cold, sun and wind. Secondary fungal infections can appear on damaged leaves, but there is no point in attempting to treat for it. The damaged leaves will fall off. Dispose of them to avoid the possibility of reinfection. The plant is clearly alive as it is putting out lots of new growth. Next winter some form of protection from a burlap barrier or evergreen boughs can help avoid a repeat.